Minimal incision maximal access MIS spine instrumentation and method

ABSTRACT

A minimal incision maximal access system allows for maximum desirable work space exposure within the incision along with maximum access to the operative field utilizing a minimum incision as small as the width of the working tube. Instead of multiple insertions of dilating tubes the design is a streamlined single entry device to avoid repetitive skin surface entry. The system offers the capability to expand to optimum exposure size for the surgery utilizing retractors depending from a bi-hinged frame having internal or external controls to control the angle and separation of the retractors. Interchangeable retractor blades can be attached to the frame. At least one retractor blade is independently controlled.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part patent application of U.S.patent application Ser. No. 11/267,618 filed Nov. 4, 2005, which is acontinuation-in-part patent application of U.S. patent application Ser.No. 11/230,420 filed Sep. 19, 2005, which is a continuation-in-partapplication of U.S. patent application Ser. No. 11/165,295 filed Jun.22, 2005, which is a continuation-in-part application of U.S. patentapplication Ser. No. 11/001,268 filed Nov. 30, 2004 now U.S. Pat. No.7,173,240, which is a divisional application of U.S. Ser. No. 10/280,624filed Oct. 25, 2002, now U.S. Pat. No. 6,849,064, the entire contents ofeach of which are incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to improvements in the field of minimalinvasive surgery and more particularly to instrumentation which allowsfor maximal access to the surgical field through the smallest possibleincision. Greater access is allowed into the working field whileenjoying the reduction of trauma and disturbance to surrounding tissues,which results in a reduced time necessary to complete the operativeprocedure, increased safety of the procedure, and further patientrecovery and rehabilitation, as well as less blood loss. Increasedaccuracy by providing an expanded working field is another goal to helpthe surgical practitioner perform well within a short time.

BACKGROUND OF THE INVENTION

Microscopic Lumbar Diskectomy techniques were developed and championedby Dr. Robert Williams in the late 1970's and by Dr. John McCullough inthe late 1980's and 1990's. For the first time since the advent ofLumbar Disc Surgery by Mixter and Barr in 1934 a method was introducedallowing Lumbar Disc Surgery to be performed through a small incisionsafely resulting in faster patient recovery and converting a two to fivehospital stay procedure virtually to an outpatient procedure.

The special retractors developed by Drs. Williams and McCullough howeverwere often difficult to maintain in optimum position and relied on theinterspinous and supraspinatus ligaments for a counter fixation pointseverely stretching these structures. This stretching along with theeffects of partial facectomy, diskectomy, removal of the ligamentumflavum and posterior longitudinal ligament contributed to thedevelopment of Post Diskectomy Instability. Taylor retractors were alsoused but were cumbersome, required larger incisions and often injuredthe facet joints.

A second generation MIS retractor system was introduced by Dr. WilliamFoley in 1997, and which was a tubular system mated to an endoscopewhich he labeled a Minimal Endoscopic Diskectomy (MED) system. Itfeatured sequentially dilating the Lumbar Paraspinous Muscles allowing aworking channel to be advanced down to the level of operation throughwhich nerve root decompression and Diskectomy Surgery could beperformed. Minor changes were made with the second generation METRxsystem. However, there were several disadvantages to the MED and METRxsystems.

In the MED and METRx systems, the cylindrical working channelconsiderably restricted visualization and passage of instruments. Italso compromised the “angle of approach” necessary for safe usage of theoperating instruments. This problem was proportionately aggravated withthe long length of the tube. This compromised visualization contributedto the following problems, including nerve injury, dural tear, misseddisc fragments, inadequate decompression of the lateral recess,increased epidural bleeding, difficulty controlling epidural bleeding,inadequate visualization of the neuroforamen, and inadequatedecompression of neuroforamen.

The repetitive introduction of successively larger dilators caused skinabrasion with the potential for carrying superficial skin organisms downto the deeper tissue layers hypothetically increasing the risk ofinfection. The learning curve for operating in a two dimensionendoscopic field proved to be arduous and contributed to the abovecomplications.

The attempted use of the METRx system for more complex procedures suchas fusion was further hazardous by inherent limitations. Endius inSeptember of 2000 then introduced a similar device which differed byhaving an expandable foot piece to allow greater coverage of theoperative field. However, the enlarged foot piece was unwieldy anddifficult to seat properly. Exposure of the angle of approach was alsolimited by having to operate through a proximal cylindrical tube withits limitations as described before. In comparison to the METRx systemthe working area was improved but access was again restricted by thesmaller proximal cylinder.

Both systems offered endoscopic capability but many spine surgeons choseto use an operating microscope or loupes to maintain 3-Dimensionalvisualization rather than the depth impaired 2-Dimensional endoscopicpresentation. Keeping debris off of the endoscopic lens has also provedto be a troubling challenge.

More recently, the third generation of MIS Retractors have been designedfor general and spine surgery (Nuvasive (Pimenta et al)), Quadrant(Branch et al), Depuy-Pipeline (Raymond et al). There have also beenmodifications of older devices offering to enter the arena of MIS SpineSurgery (Koros). The plethora of proposed surgical retraction devicesand methods have led to a confusion of meaning of the “MIS SpineSurgical Technique.” Surgical incisions of up to five inches in lengthhave been described for MIS Surgery. Usage of the term “MIS Surgery” asapplied to spine surgery, appears to have evolved to mean a surgicalincision less than the traditional one or two levels above and below thesurgical field of interest. However, the combined length of twoincisions (right and left) often is longer than the single midlineincision. The true advantage of MIS Surgery over the traditionaltechnique is the specificity of exposure such that only the requiredamount of retraction of soft tissue is used to safely accomplish thespecific surgical procedure.

Ideally, there are certain prerequisites for a MIS spine retractor thatshould be fulfilled in order to accomplish the objective that only therequired amount of retraction of soft tissue is used:

-   -   1. The retractor must provide sufficient direct visualization of        the neural elements, related blood vessels, and bony landmarks        to accomplish safe spine surgery.    -   2. The retractor should require the least amount of resection of        adjacent tissue muscle, fascia, bone, and joints to accomplish        the task.    -   3. The retractor should be self-retaining instead of hand-held        (Ritland).    -   4. Deployment of the surgical retractor should be able to be        prompt and precise in location.    -   5. The retractor should be easy to adjust for length, width, and        angle of exposure.    -   6. The retractor support, such as a frame, must have the        capability to lie flat to the surface contour of the body so        that the attached retractor blades could be as short as        possible.    -   7. The retractor support, such as a frame and blades must be        stable once optimum surgical exposure is obtained.    -   8. There should be a minimum of “fiddle factor” so the surgeons        attention can remain focused on the operation and not distracted        by the complexity of using the retractor.    -   9. The retractor must be “strong enough” in design not to flex        and lose exposure.    -   10. Particularly for surgery of the posterior lumbar spine, the        retractor must be designed to counter the powerful paraspinal        muscle resistance without using large incremental changes (e.g.        widely spaced ratcheted gap).    -   11. With longer exposure length, there must be an efficient        means to retract muscle that encroach between the retractor        blades.    -   12. The need for ancillary equipment such as light source        attachments, etc., are self evident.

Currently available surgical retractor systems fail to fulfill all ofthe above requirements. Consequently there is a severe need forstructures and procedures to meet such requirement.

Due to the spine surgeon's desire to utilize the advantages of MISSurgery to evermore complex procedures, the MIS Surgical Retractors haveevolved to attempt accommodate this need. For example. the Danek MEDTube evolve to the X-Tube and then to the Quadrant system (U.S. Pat. No.6,945,933 to Branch et. al, Dewey et al). Still other retractorinventions have come to market including the three-bladed, Nuvasivedesign for the lateral approach to the Lumbar Interbody Space, the Depuy“pipeline” retractor, a highly complex four-bladed retractor system witha curved ratchet arm, the Stryker Luxor. None of the above retractorSystems incorporate the full complement of prerequisites listed above.

The Branch, et al. System's new retractor creates a “working channel”with insertion of sequentially larger dilating tubes. This method ofintroduction into the body while acceptable for use with an enclosedtube encounters problems when the newer systems with retractor bladeswhich can be opened apart are utilized. With the serial dilationtechniques the strong fascia and paraspinal muscles have remainedintact, and therefore a monumental battle develops between theseparating blades and the intact muscle and fascia resisting theexpansion. This necessarily results in tearing and shredding of themuscle as the blades are forced apart.

This is acknowledged by Branch et al '933 reference at page 10,paragraph 2. “In use, the resistance to retraction provided by thetissue may prevent distal ends from separating as far as proximal ends.”In the Branch/Dewey system this is always the case when spine surgery isattempted at more than one level. Since the muscles have retained theirstrong attachment to the bone, forcing of the retractor blades apartnecessarily requires ripping and shredding of the muscles and associatedblood vessels and nerves.

The Quadrant System retractor blade separation is also based on astraight ratchet bar and therefore cannot accommodate for Lumbarlordosis which is often forty degrees at the lumbosacral junction. Thisrequires retractor blades to be longer as the frame tends to “ride upfrom the surface of the skin” due to the curvature of the surfaceanatomy.

The retraction blades of the Quadrant system are also cantilevered aconsiderable distance from their attachment point on the ratchet barcreating unwanted movement, stress, and loss of muscle retractioncompromising exposure. Applying a force from such a distance tends to(1) lose control of soft tissue retraction and therefore compromises the“working channel”, (2) loads stress into bending and compression momentsof a mechanical apparatus, and (3) having the mechanical apparatus blockthe surgical area while it is being employed. Therefore, the Quadrantsystem's retractor blades location at a considerable distance from itsbase attachment point on its ratchet bar creates a long lever arm momentwhich lends instability to the retractor blades. The Branch referencealso shows a curved frame but this cannot adjust to different lordoticangles of the patient's posterior lumbar area.

The Pipeline retractor, while adequate for one level posterior lateralfusion procedure, has the deficiencies as described in the QuadrantSystem because of the serial dilation introduction method and suffersfrom negative effects of its extreme complexity. Raymond attempts toaddress the need to accommodate for lower lumbar lordosis by using acurved ratchet frame, but their fixed curvature cannot adjust todifferent lordotic angles. In addition, the Pipeline retractor hasproven extremely difficult to spread the retractor blades up an inclinedslope along the arc of the ratchet arms against the strong resistance ofthe muscle and fascia even using a separate spreader device. ThePipeline device also has proven to be so complex that it is verydifficult and time consuming to set up, operate, and learn to use.

The Nuvasive Retractor (Pimenta) is suitable for the lateral approach tothe L2, L3 and L4 levels for which the retractor was designed. Thedeficiencies of a three bladed retractor like Nuvasive's become apparentwhen used for other procedures such as a posterolateral lumbar fusion.If the Nuvasive retractor is deployed such that the middle blade islateral, then visualization of the spinal canal can be difficult. If theNuvasive middle blade is placed medial, there is significant muscleencroachment as the blades are spread apart.

Another reference, Cocchia's U.S. Pat. No. 6,224,545 has a number ofshortcomings, including (1) a surgical frame having no structure toallow flexion and extension, (2) retractor blades which are rotated withan awkward force plate device, and (3) the knobs used to controlmovement of the device are difficult to use due to the proximity on thepatient's skin and inability to apply adequate torque.

Further, Cocchia's device requires a completely open slot in the arms ofthe main frame, along which is run a cylindrical guide bar. The Cocchiadevice also requires two additional “traveling rods” on the threadassembly cross piece to keep the moving parts from binding. Coccia'sdesign also has an exposed, open end of the screw device which can tearsurgical gloves and tissues predisposing to infection.

Coccia's use of a force plate method to provoke angulation of theretractor blade, also lacks the control to return to neutral fromoutward deflection. The force control of Coccia's device furthermoredoes not contemplate force movement to an inwardly angled position. As aresult, Coccia's device is impractical for advanced retraction needs.

As discussed above, it is advantageous to have a retractor frame thatcan adjust to the body surface where the surgery is being performed.Historically, several retractors for general purposes have had a hinge,usually on the handles of the retractor (Beckman) or on the frame(Koros, Watanabe) to lower a portion of the retractor out of the way ofthe surgeon's hands. The hinges did not serve the purpose of contouringthe device to the surface of the body.

The axis of rotation of these hinge devices is therefor cephalo-caudalor in the longitudinal axis of the body. Turning these retractors 90°would be counter to the general intended use of these retractors.Furthermore, the retractor hinges were “free moving” and did not havecontrol devices.

The Bookwalter retractor did have two hinges connecting two halves of acircular or elliptical frame with an angular control device. Theangulation was controlled by interdigitating rings which were lockedinto position with thumbscrews. This allowed flexion and extension ofthe basic hoop frame, but required loosening of the thumbscrews,disengaging the ratchets, adjusting to a new position, reengaging theratchets and re-tightening the screws. This arduous process is allowablefor abdominal surgery but is unacceptable for MIS spin surgery.

In order to attain ideal exposure at the surgical work area, it is alsoimportant to have customized retractor tips. The value of “docking” ofthe distal end of the retractor has been described for closed tube MISretractor systems by Michelson (U.S. Pat. No. 6,080,155) and Simonson(U.S. Pat. No. 7,008,431). These concepts have not been able to beemployed in higher level retractor systems.

SUMMARY OF THE INVENTION

The system and method of the invention, hereinafter minimal incisionmaximal access (MIMA) system, includes a surgical operating system thatallows for maximum desirable exposure along with maximum access to theoperative field utilizing a minimum incision to be described.

The MIMA system disclosed offers advantages over other MIS spineretractor systems in several respects.

1. Instead of multiple insertions of Dilating Tubes, the Invention is astreamlined single entry device. This avoids repetitive skin surfaceentry for one level procedures.

2. For greater exposure, the MIMA system contemplates soft tissuerelease prior to deployment of the retractor by using a fascialincisor/dissector.

3. The MIMA system offers the capability to expand to optimum exposuresize for the surgery utilizing hinged bi-hemispherical or oval WorkingTubes applied over an introducer Obturator which is controllably dilatedto slowly separate muscle tissue.

4. The MIMA system maximizes the deeper surgical area with fineadjustment capability.

5. The MIMA system provides expanded visual and working field to makesthe operative procedure safer in application and shorten the surgeons'slearning curve because it most closely approximates the openmicrodiskectomy techniques.

6. The MIMA system has a tapered ended Obturator which allows for tissuespread on entry.

7. The MIMA system controls muscle oozing into the operative field whichis controlled by simply opening the tubes further. This also therebycontrols the bleeding by pressure to the surrounding tissues.

8. In contrast to the closed cylindrical tube based systems such as theMETRx and Simonson the MIMA system offers a larger working area inproportion to the entry opening. The enlarged footprint of the MIMAsystem is a major difference from any other minimal access system.

9. The expandable design of the MIMA system allows for excellentexposure for more complex procedures such as fusion and instrumentationincluding TLIF, PLIF, and TFIF (Transfacet Interbody Fusion), as well asallowing application for surgery on other areas of the body. Forexample, MIMA system can be used for anterior lumbar interbody fusion beit retroperitoneal, transperitoneal or laproscopic from anterior orlateral approaches

10. Another advantage of the MIMA system is the customized retractortips. For example, in lumbar microdiskectomy, the medial oval cutout ofthe retractor blade forming the working tube allows more central dockingon the spine which is problematic for other devices. A medializeddocking provides access for easier and better and safer dural retractionto address midline pathology.

11. The anti-reflective inner surface of the retractor blades whicheliminates unwanted glare.

12. The MIMA system includes the slanted and contoured distal end of theretractor blade which allows minimal resistance for entry andadvancement to the docking site.

13. Another advantage MIMA system is the provision for different shapedretractor blades (round, oval, flat, etc.) According to the needs of thesurgical procedure and location. This minimizes unnecessary musclespread and resection.

14. The larger retractor blade of the MIMA system also features one ortwo “skirts” to cover the lateral aperture created by the spread of thetwo retractor blades when opened. This prevents soft tissue and muscleingress into the exposure zone. The skirts are attached to the workingtube either at the hinge or on one or both of the two halves of theretractor blades.

15. An advantage of the MIMA system is the provision of a modular designin which the retractor blades can be quickly removed, changed andreapplied. In this version the proximal port can also be modular andchangeable to fit the needs of a specific surgical procedure.

16. The MIMA systems retractor blades can be made out of metal, ceramicor plastic, can be opaque or translucent, and can have tips of differentshapes for different applications.

17. The provision of snap lock connections of the major parts of theInvention provides for easy assembly and disengagement for cleaning andsterilization purposes.

18. The obturator of the MIMA system is cannulated for carrying acentral Guide Pin Passage. It has a Handle component which remainssuperficial to the skin. The obturator houses an internal hinge devicewhich allows for spread of the two obturator tips.

19. Another advantage of the MEMA system is the uniquely designed facialincision and dissection which creates the least traumatic way totraverse the muscle layer by incision of the firm fascia and aponeurosissplitting the muscle in the direction of its fibers and the technique ofdetaching the muscle attachment to the bone rather than tearing andripping of the muscle.

20. A further advantage involves the possibility that the improvedretractor can range in complexity from a single axis single hinge,two-blade retractor which allows expansion at the deep end of theretractor blades to other versions, but which will also permitenlargement of the proximal opening as well.

21. Another advantage is the use of a simple modification of aGelpi-type retractor enables retraction perpendicular to the directionof spread of the main retractor.

22. Another advantage is that in further embodiments, a double support,such as a frame can be connected by a controllable hinge which allowsflexion and extension to accommodate the contour of the patient's bodysurface.

23. Another advantage is that the retractor blades are interchangeableand have independent control features.

24. Another advantage is that overall, the focus of this invention'sdesign has been to maintain simplicity and efficiency in the use of theretractor.

25. A further advantage of our approach (both retractor and surgical) isachieved by incising the fascia and spreading the muscle in thedirection of its fibers before the retractor is deployed.

Advantages of the MIMA System

In contrast to the shortcomings of presently commercially availableretractors, the inventive retractor offers the following advantages:

-   1. Atraumatic one step entry into the body.-   2. Pre-deployment soft tissue is released in a controlled    least-traumatic fashion.-   3. Streamlined retractor design can accomplish tissue retraction    with only three controls.-   4. Micro-control feature with a simple screw-activated design gives    precise control and mechanical advantage.-   5. In one embodiment, a “hands away from the body design” utilizes    an innovative ratchet.-   6. The frame/support is connected by micro-adjustable hinge to    customize flexion or extension to match the body contour. The    micro-controllable hinge design of the present invention allows the    resting of the support structure, such as a frame, close to the    patient's skin surface so that it is as “flat” or close to the body    surface as possible. This allows for the shortest working depth    which maximizes the visual line of sight into the working area. The    shortest working depth allows for shorter instruments to be used and    decrease the chance of inadvertent surgical mistakes.-   7. Customized retractor blade tips to “dock” to the surgical work    site.-   8. Modular, easy to change design for the retractor blades and tips.-   9. Method to retract muscle ingress by customized deep Gelpi-type    retractor customized for use with the retractor of the invention.-   10. MIS retractor design applicable for surgery to several areas of    the body and specifically for the lumbar spine allowing access for    up to a three level instrumented fusion which is not currently    possible with any other MIS spinal retractor.-   11. The “screw-in-frame” design provides a simple yet powerful way    to open or close at least one retractor blade. Turning of the    threads allows a slow separation of the muscle, fascia, blood    vessels and nerves, instead of a forceful fixed magnitude    incremental jumps in separation.-   12. The control grooves on either the retractor legs or the first    inner translatable frame member, in the case where a frame member    enables quick change out of retractor blades, guides and controls    the opening and closing of at least one retractor blade housing in a    stable, positive, strong, controllable manner.-   13. A screw and captured head design enables a continuously viewable    positive control with visual verification of operation. The surgical    practitioner can see the position of pivoting members, which gives    an instant feedback of the expected ease or resistance of operation.    Further, the screw and captured head design, with a threaded member    operating from within internal threads of a rotational block    fitting, where the threaded member has an externally viewable ball    fitting structure fitting within a rotational block fitting provides    a control linkage which is nearly 100% exposed for sterilization    purposes. The result is a set of structures whose integrity are    immediately knowable, and which give a positive, exposed manner of    interactive operation.-   14. A new, bidirectional ratchet uses a custom bi-directional    ratchet having a hex or other shaped head. A flow through design    provides complete wettable sterilization, and a quick dis-assembly    construction provides complete break down and re-assembly for fine    cleaning and service.-   15. The designs of the retractor system enable the surgical    practitioner to operate around the device without exposing the    surgeons hands and gloves to surfaces which might damage the gloves    and expose the patent's tissues to infection. Further, the    bidirectional ratchet enables even further isolation of the surgeons    hands and gloves from mechanical surfaces and structures which might    otherwise compromise the sterile integrity of the operation.-   16. The use of a bidirectional ratchet which can be quickly mated to    actuation points, used and then moved to another point, enables the    surgical practitioner to focus more on each element of adjustment    and upon satisfaction of proper adjustment, remove the bidirectional    ratchet from the surgical field during the operation.-   17. The importance of the use of custom designed retractor blade    tips which are specific for the needs of a particular surgical    procedure cannot be underestimated. A bi-valved tubular blade with    medial cutout, for example, is ideal for a one level lumbar    microdiscectomy because of maximum lateral soft tissue retraction    with good access to the spinal canal provided by the medial cutout.    In another example, an inverted “U” cutout with a modified medial    cutout is ideal for TLIF procedures as it allows for “docking” of    the retractor tips on the prominence of the facet joints or    transverse process, and still provides good access to the spinal    canal and is well positioned for pedicle screw insertion.-   18. Quick blade change can be combined with differential retractor    blade use where one type of blade is used on one portion of the    retractor and another type of blade is used on the opposite portion    of the retractor, or elsewhere.-   19. Quick change locking screws or latches, enable the surgical    practitioner to pull and examine, and then change retractor tips    without having to fuss with small parts or tiny mechanisms which    could come loose. As by example, there are times when tubular shaped    retractor blades are preferable while at other times a “U” shaped or    a flat blade is preferable. The flange on the proximal end of the    retractor blades will provide for a strong and very stable    attachment structure. The use of a quick turning pair of set screws    for each side of the flanges provides a positive lock and unlock    with clear visual indication of lock. This further gives confidence    that the positive lock will enable the secure retractor blades to be    urged apart against strong resistance of the muscle and other soft    tissue. Other types of locks are possible including spring urged    locks, detent locks and the like. The flange on the proximal end    provides for a strong and stable attachment.-   20. Customized deep Gelpi-type retractors can be advantageously    utilized with the retractor systems described to allow wider    medial-lateral soft tissue retraction than the boundaries of the    retractor frame. This opens up the central part of the operative    field, retracting tissue that would otherwise encroach into the    surgical field. The contour of the retractor stems also accommodates    changing depth needs.-   21. The simplicity of design and usage, including the combination of    all parts described herein has culminated in a strong, reliable,    versatile MIS retractor system that is easy to master and use. For    those skilled in the surgical arts, this multi-faceted feature is    highly prized and appreciated as it can allow for shorter operative    time, decreased blood loss, reduced tissue trauma and less surgical    error.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, its configuration, construction, and operation will bebest further described in the following detailed description, taken inconjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a working tube with an angled uppersection and shown in position with respect to an obturator insertableinto and workable within the working tube;

FIG. 2 is a perspective assembled view illustrating the relativepositions of the obturator and working tube;

FIG. 3 is a perspective assembled view illustrates the position of theobturator after it has been inserted into the working tube;

FIG. 4 is a view taken along line 4-4 of FIG. 2 and looking into theworking tube of FIG. 1;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 2 and lookinginto the hinge of working tube of FIG. 1, illustrating its hingeconnections;

FIG. 6 is an side end view of the working tube of FIGS. 1-5 andillustrating predominantly one of the rigidly connected halves of theinvention;

FIG. 7 is a side sectional view taken along line 7-7 of FIG. 6 andshowing the internal bearing pivot;

FIG. 8 is a side sectional view taken along line 8-8 of FIG. 5 andillustrating a option for external bevel for the working tube;

FIG. 9 is a side view of the working tube of FIGS. 1-8 shown with thelower portions in parallel alignment and the upper portions angled withrespect to each other;

FIG. 10 is a side view of the working tube as seem in FIG. 9 and shownwith the lower portions in an angled relationship and the upper portionsin a closer angled relationship with respect to each other;

FIG. 11 is a side view of the working tube as seen in FIGS. 9 and 10 andshown with the lower portions in a maximally angled relationship and theupper portions in parallel alignment signaling maximal spread of thelower portions in bringing the upper portions into parallel alignment;

FIG. 12 is a side view of the obturator of FIG. 1 and seen in anassembled view and emphasizing a through bore seen in dashed lineformat;

FIG. 13 is a side view of the obturator of FIG. 11 as seen in anassembled view but turned ninety degrees about its axis and emphasizingthe through bore;

FIG. 14 shows a side view of the obturator 33 of FIG. 13 with thespreading legs in an angled apart relationship;

FIG. 15 is a sectional view taken along line 14-14 of FIG. 12 and givesa sectional view from the same perspective seen in FIG. 14;

FIG. 16 is a view of the obturator similar to that seen in FIG. 15, butturned ninety degrees along its axis and illustrates the wedge as havinga narrower dimension to lend internal stability;

FIG. 17 is a closeup view of the external hinge assembly seen in FIG. 1and illustrates the optional use of a plug to cover the exposed side ofa circular protrusion;

FIG. 18 is a view taken along line 18-18 of FIG. 11 and illustrates theuse of an optional skirt having flexible members which spread from aninitial curled position to a straightened position to better isolate thesurgical field;

FIG. 19 is a view of the lower tube hemicylindrical or curved portions65 and 69 in a close relationship illustrating the manner in which theskirts sections within their accommodation slots areas;

FIG. 20 is a cross sectional view of the a patient and spine andfacilitates illustration of the general sequence of steps taken for manyprocedures utilizing the minimal incision maximal access systemdisclosed;

FIG. 21 illustrates a fascial incisor over fitting a guide pin andfurther inserted to cut through external and internal tissue;

FIG. 22 illustrates the assembled Working Tube—Obturator being insertedinto the area previously occupied by the fascial incisor and advanced tothe operative level lamina;

FIG. 23 illustrates the obturator 33 being actuated to a spreadorientation to which automatically actuates the working tube to a spreadorientation;

FIG. 24 is a view of the working tube 35 is in place and supported, heldor stabilized in the field of view by a telescopy support arm andengagement, the opposite end of the stabilizing structure attached tothe operating table;

FIG. 25 illustrates further details of the support arm seen in FIG. 24,especially the use of a ball joint;

FIG. 26 illustrates a side view of the assembly seen in FIG. 25 is seenwith an adjustable clamp operable to hold the working tube open at anyposition;

FIG. 27 is a top view looking down upon the adjustable clamp seen inFIGS. 25-26 and shows the orientation of the working tube and adjustableclamp in fully closed position;

FIG. 28 shows a variation on the obturator seen previously in FIG. 1 andillustrates the use of handles which are brought together;

FIG. 29 illustrates a further variation on the obturator seen previouslyin FIG. 1 and illustrates the use of a central ball nut;

FIG. 30 is a sectional view taken along line 30-30 of FIG. 29 andillustrates the use of a central support block to support the centralthreaded surface;

FIG. 31 is a top view of a thin, inset hinge utilizable with any of theobturators herein, but particularly obturators of FIGS. 1 and 29;

FIG. 32 is a sectional view of the obturator of FIG. 1 within theworking tube of FIG. 1 with the wedge 51 seen at the bottom of aninternal wedge conforming space;

FIG. 33 illustrates the obturator seen in FIG. 32 as returned to itscollapsed state.

FIG. 34 illustrates a top and schematic view of the use of a remotepower control to provide instant control of the working tube using anadjustable restriction on the upper angled curved portions of theworking tube;

FIG. 35 is a view taken along line 35-35 of FIG. 34 and illustrating themethod of attachment of the cable or band constriction;

FIG. 36 is a mechanically operated version of the nut and boltconstriction band seen in FIG. 25;

FIG. 37 is an isolated view of two curved tube sections shown joined ina tubular relationship and indicating at least a pair of pivot axes oneach curved tube section;

FIG. 38 is an isolated view of two curved tube sections as seen in FIG.38 which are angularly displaced apart about a shared first pivot axison each of the curved tube sections;

FIG. 39 is an isolated view of two curved tube sections as seen in FIGS.38 and 39 which are angularly displaced apart about a shared secondpivot axis on each of the curved tube sections;

FIG. 40 is a plan view of a given width supplemental side shield havinga width of approximately the separation of the curved tube sections asseen in FIG. 39;

FIG. 41 is a top view of the supplemental side shield of FIG. 40;

FIG. 42 is a pivoting thread support system in which a pair of opposingflank threaded members operate a pivoting support and are connected by agear mechanism shown in exaggerated format to give single knobseparation control;

FIG. 43 illustrates a surrounding support system utilized to provide andenable pivoting and translation;

FIG. 44 illustrates a view looking down into the structure of FIG. 43shows the overall orientation and further illustrates an optionalsecuring tang;

FIG. 45 illustrates a simplified control scheme in which simplicity isemphasized over controllability with less moving parts and expense;

FIG. 46 illustrates a further embodiment of a manipulative structurewhich works well with the structure of FIG. 45;

FIG. 47 illustrates another possible realization which combines thecontrol mechanisms of selected portions of FIGS. 37-46, combined withother possible options;

FIG. 48 illustrates a side view of the side shield seen in FIG. 47;

FIG. 49 illustrates one possible configuration for a variable depthguide which is utilizable with any of the devices seen in FIGS. 37-46 orany other tubular, minimally invasive system;

FIG. 50 is a vertical plan view of an expandable frame system which usesdetents to set the frame size and which uses an angular distributionsystem;

FIG. 51 is a top view of the system of FIG. 51 in an expanded position;

FIG. 52 is a side view of the system of FIGS. 50-52;

FIG. 53 illustrates a top view double pivot hinge fitting andillustrating the gear surfaces;

FIG. 54 illustrates the action of the pivot hinge which produces an evenangular deflection;

FIG. 55 illustrates a top view of a bookwalter device mounted atop acentral hinge box seen in FIG. 53;

FIG. 56 is a top view of a retractor system employing many of thecomponents seen in FIGS. 50-52 for applying force from a distance;

FIG. 57 is a top view of a curved retractor tube extension;

FIG. 58 is a side sectional view of the curved retractor tube extensionof FIG. 57 attached to the curved tube seen in FIG. 52;

FIG. 59 is a view looking down into the inside of the curved retractortube extension of FIGS. 57 and 58;

FIG. 60 is a view looking down onto the outside of the curved retractortube extension of FIGS. 57-59;

FIG. 61 is an exploded view of a further embodiment of a frame retractorsystem utilizing a base frame and raised tube manipulator;

FIG. 62 is a perspective view of the frame retractor system seen in FIG.61;

FIG. 63 is a perspective view of the frame retractor system from thesame perspective as seen in FIG. 61 and illustrated as being fitted witha fiber optic illuminator;

FIG. 64 is a top view of the frame retractor system seen in FIGS. 61-63;

FIG. 65 is a bottom view of the frame retractor system seen in FIGS.61-64;

FIG. 66 is a side view of the frame retractor system seen in FIGS.61-65;

FIG. 67 is a perspective view of a wire retractor utilizable with theframe retractor system of FIGS. 61-67;

FIG. 68 is an isolated view of the ends of the wire retractor shown inan opening pattern;

FIG. 69 is an isolated view of the ends of the wire retractor shownsuperimposed in a crossing pattern to reduce the profile for entry intothe frame retractor system of FIGS. 61-66;

FIG. 70 is a side view of the frame retractor system seen in FIGS.61-63, and illustrating portions of an optional wire guide retractor;

FIG. 71 illustrates the frame retractor system and wire retractor shownwith respect to tissue;

FIG. 72 illustrates the wire retractor being opened to an open positionwithin the frame retractor system and within the tissue;

FIG. 73 illustrates a plan view of a manual tool with a main handleportion and interfitting blades;

FIG. 74 illustrates a different interchangeable blade attachment for themanual tool of FIG. 73;

FIG. 75 is a further embodiment of the manual tool seen in FIGS. 73 and74;

FIG. 76 illustrates a view looking into the slip fitting of the manualtool of FIG. 75;

FIG. 77 illustrates a top view of a further embodiment of a frameretractor system;

FIG. 78 illustrates a bottom view of the embodiment of FIG. 77;

FIG. 79 illustrates a sectional view taken along line 79-79 of FIG. 77;

FIG. 80 illustrates a sectional view taken along line 80-80 of FIG. 77;

FIG. 81 a top semi sectional detail view of the inside corner of thefirst inner translatable frame member seen in FIGS. 77 & 78 and shown inlocked position;

FIG. 82 is a view in accord with FIG. 81 but illustrating the unlockedposition;

FIG. 83 illustrates a top view of a first generally curved retractormember utilizable with a frame retractor system;

FIG. 84 illustrates a top view of a second retractor member which may beutilizable with the first retractor member of FIG. 83;

FIG. 85 illustrates a left side view of the first retractor member ofseen in FIG. 83;

FIG. 86 illustrates a right side view of the second retractor member ofseen in FIG. 84;

FIG. 87 illustrates a rear view of the second retractor member of FIGS.84 and 86;

FIG. 88 illustrates a top view of a first generally rectangular profileretractor member having curved edges and utilizable with a frameretractor system;

FIG. 89 illustrates a top view of a second retractor member utilizablewith the first retractor member of FIG. 88;

FIG. 90 illustrates a left side view of the first retractor member ofseen in FIG. 88;

FIG. 91 illustrates a right side view of the second retractor member ofseen in FIG. 89;

FIG. 92 illustrates a rear view of the second retractor member of FIGS.89 and 91;

FIG. 93 illustrates a right side view of the a retractor member having abulge near its lower extent;

FIG. 94 illustrates a rear view of the retractor member of FIG. 93;

FIG. 95 illustrates a right side view of the a retractor member having agrossly but gently serrated lower shape;

FIG. 96 illustrates a rear view of the retractor member of FIG. 93;

FIG. 97 illustrates a right side view of the a retractor member having arounded cutout at its lower edge;

FIG. 98 illustrates a rear view of the retractor member of FIG. 97;

FIG. 99 is a left side view of the frame retractor system of FIGS. 77 to82 in which the retractor members are shown parallel and separated fromeach other;

FIG. 100 is a right side view of the frame retractor system similar tothat seen in FIG. 99 and in which the retractor lower extension membersare shown parallel and separated from each other;

FIG. 101 is a right side view of the frame retractor system similar tothat seen in FIGS. 99 to 100 and showing angular displacement of thefirst main frame member with respect to the second main frame member;

FIG. 102 is a right side view of the frame retractor system similar tothat seen in FIGS. 99 to 101 and showing angular displacement of thefirst inner pivotable frame member causing the lower extension membersto angle away from each other;

FIG. 103 is a right side view of the frame retractor system similar tothat seen in FIGS. 99 to 102 and showing angular displacement of thefirst inner pivotable frame member causing the lower extension membersto angle toward each other;

FIG. 104 is a right side view of the frame retractor system similar tothat seen in FIGS. 99 to 103 and showing retractor lower extensionmembers parallel and adjacent each other;

FIG. 105 is a right side view of the frame retractor system similar tothat seen in FIGS. 99 to 104 and showing retractor lower extensionmembers parallel and displaced from each other;

FIG. 106 illustrates a top view of frame retractor system similar tothat seen in FIGS. 99 to 105 and showing retractor lower extensionmembers parallel and in adjacent relationship as seen in FIG. 104;

FIG. 107 illustrates a right side view of frame retractor system similarto that seen in FIGS. 99 to 106 and showing an obturator used inconjunction with the frame retractor;

FIG. 108 illustrates a left side of the frame retractor system similarto that seen in FIGS. 99 to 107 and showing disengagement of the angulardisplacement mechanism to permit free angular movement;

FIG. 109 illustrates a top view of a variation on the frame retractorsystem in FIGS. 99 to 108 as having two external controls moved insidethe outer surface of the frames and including a worm gear system forangular adjustment of the retractor members and first and second mainframe members;

FIG. 110 is a bottom view of the retractor system seen in FIG. 109;

FIG. 111 is a bottom view of the retractor system seen in FIGS. 109 and110;

FIG. 112 is a left side view of the retractor system seen in any of theFIGS. 99 to 111 and in which the obturator and working blade of FIG. 1is supported by the first and second main frame members where theinterfitting retractor members have been removed;

FIG. 113 is a top view of the arrangement seen in FIG. 112;

FIG. 114 illustrates a side view looking into and partially through aratchet actuation tool utilizable for force adjustment in a sterilesurgical environment;

FIG. 115 illustrates a view of the ratchet actuation tool including thefirst plate & supported components seen with the second plate removed;

FIG. 116 illustrates a plan view of the ratchet actuation tool firstplate;

FIG. 117 illustrates a plan view of the ratchet actuation tool secondplate;

FIG. 118 illustrates a sectional view taken along the midline of theratchet actuation tool first plate;

FIG. 119 illustrates a sectional view taken along the midline of theratchet actuation tool second plate;

FIG. 120 illustrates an end view looking into the first socket;

FIG. 121 illustrates a plan view of the first socket;

FIG. 122 is a top end view of the first socket seen in FIGS. 120 and121;

FIG. 123 is a rear end view of the second socket;

FIG. 124 illustrates a plan view of the second socket;

FIG. 125 illustrates an end view looking into the second socket seen inFIGS. 123 and 124;

FIG. 126 illustrates a plan view of the ratchet sprocket engagementhead;

FIG. 127 illustrates an end view of the ratchet sprocket engagementhead;

FIG. 128 illustrates a plan view of the sprocket;

FIG. 129 illustrates a plan view looking downward on the spacer clip;and

FIG. 130 is an exploded sectional detail illustrating the relationshipof the first and second plates, how the spacer clip is secured to thefirst plate, how the spacer clip secures the second plate and how thespacer clip acts to control the spacing between the first and secondplates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The description and operation of the minimal incision maximal accesssystem will be best described with reference to FIG. 1 and identifying ageneral system 31, although FIGS. 1, 2 & 3 should be referencedsimultaneously. System 31 includes an obturator 33 and a working tube35. The orientation of the obturator 33 is in a slightly displaced froma position of alignment with the working tube 35 for entry into workingtube 35 and to provide the initial carefully controlled force forspreading the working tube 35, as will be shown.

Obturator includes an upper control housing 37 and a pair of spreadinglegs 39 and 41. The spreading legs 39 and 41 are seen as coming togetherto form a conical tip and thus have hemi-conical end portions. Thespreading legs 39 and 41 over fit the attachment leg portions 43 and 45,respectively. At the top of the upper control housing 37 a boss 47surrounds and supports the extension of a control shaft 49. A knurledthumb knob 50 sits atop the control shaft 49 to facilitate controlledturning of the control shaft 49 to control the degree of spreading ofthe spreading legs 39 and 41. Thus spreading can be controlledindependently of pressure applied along the length of the obturator 33.

Below the upper control housing 37 is the bottom of the control shaft 49which operates against a wedge 51. The wedge 51 operates within a pairof opposing slots 52 in an upper portion 53 of the overfit attachmentleg portions 43 and 45. The lower ends of the overfit attachment legportions 43 and 45 include insertion tangs 55 which fit within insertionslots 57 of the spreading legs 39 and 41. The overfit attachment legportions 43 and 45 are pivotally attached to the upper control housing37 internally by pivot blocks 59 which fit within access apertures 60.

The working tube 35 has a first lower extending connection tang 61 and asecond lower extending connection tang 63. First lower extendingconnection tang 61 connects into a slot 64 of a lower tube curvedportion 65. The first lower extending connection tang 61 is fixed to anupper angled curved portion 67. The second lower extending connectiontang 63 connects into a slot 68 of a lower tube curved portion 69.Second lower extending connection tang 61 is fixed to and an upperangled curved portion 71. The upper angled curved portion 67 may have areinforced wear plate 73 for applying upper pressure and force on theupper angled curved portions 67 and 71 toward each other to cause thefirst and second lower extending connection tangs 61 & 63 and theirconnected lower tube curved portions 65 and 69 to be urged away fromeach other.

At the side of the working tube 35 at the transition between the upperangled curved portions 67 and 71 and at a point just above the first andsecond lower extending connection tangs 61 & 63 is an external hingeassembly 77. Hinge assembly 77 may include an optional first guide plate79 (seen in FIG. 2) and first circular protrusion 81 attached to upperangled curved portions 67, and a first slotted plate 83 positionedadjacent to first guide plate 79 and having a slot partially surroundingthe circular protrusion 81.

Upper angled curved portion 71 has a pair of spaced apart facingsurfaces facing a matching pair of facing surfaces of the upper angledcurved portion 67, of which a dividing line 85 is seen. Upper angledcurved portions 67 and 71 are be brought together to cause the first andsecond lower extending connection tangs 61 & 63 and their connectedlower tube curved portions 65 and 69 to spread apart.

In the view of FIG. 1, the first and second lower extending connectiontangs 61 & 63 are shown in a spread apart relationship. A locking pin 87is seen which can be used to engage angularly spaced apart apertures inthe circular protrusion 81 to provide a detent action to hold theworking tube 35 in various degrees of spread. Also seen is a slightexterior bevel 89 on the lower tube curved portions 65 and 69.

Note the angled separation of the upper angled curved portions 67 and71. The angle of the opposing surfaces (only opposing surface 91 is seenin FIGS. 2 & 3) equals the angle of spread of the first and second lowerextending connection tangs 61 & 63.

Referring more closely to FIG. 2, a perspective assembled viewillustrates the relative positions of the obturator 33 and working tube35 in a position for the obturator 33 to be inserted into the workingtube 35 and before any spreading takes place.

Referring to FIG. 3, a perspective assembled view illustrates theposition of the obturator 33 after it has been inserted into the workingtube 35 and again before any spreading takes place. Note that the pivotaxes of the first and second lower extending connection tangs 61 & 63are on par with the pivot axes of the insertion tangs 55. The tip of theobturator 33 extends slightly beyond the bottom most part of the workingtube 35 so that the completed assembly can be smoothly urged past muscleand other tissue.

Referring to FIG. 4, a view taken along line 4-4 of FIG. 1 is a viewlooking down into the working tube 35. Other features seen include awear plate 93 located on the upper angled curved portion 71. In both ofthe wear plates 73 and 93 a universal port 94 is provided as a bore forinsertion of a tool or lever to assist in bringing the upper angledcurved portions 67 and 71 into a tubular relationship. Further, anidentical hinge assembly 77 on the side opposite that seen in FIG. 1 isshown with the same numbering as the components which were seen in FIG.1.

Also seen are the pair of opposing surfaces 91 on upper angled curvedportion 71 and a pair of opposing surfaces 97 on upper angled curvedportion 67. Also seen is a central working aperture 99.

Referring to FIG. 5, a view taken along line 5-5 of FIG. 1 is asectional view looking down into the working tube 35. The connectivityof the structures seen in FIG. 4 are emphasized including the connectionof circular protrusion 81 to the upper angled curved portion 71, and theconnection of first slotted plate 83 to upper angled curved portion 67,and which is indicated by the matching section lines. Further, anidentical hinge assembly 77 on the side opposite that seen in FIG. 1 isshown with the same numbering as the components which were seen in FIG.1.

Referring to FIG. 6, a view of one end of the working tube 35illustrates predominantly the second angled half portion 63. Elementsseen in FIGS. 1-3 are made more clear in FIGS. 6-11.

Referring to FIG. 7, a side sectional view taken along line 7-7 of FIG.6 and shows the internal bearing pivot consisting of a slightly greaterthan hemispherical side bump projection 101 located on upper angledcurved portion 71, and a slightly less than hemispherical side circulargroove 103 located on upper angled curved portion 67. Also seen is theinterconnect slots 64 and 68 as well as the first and second lowerextending connection tangs 61 and 63. In the showing of FIG. 7 anexternal bevel 105 is utilized

Referring to FIG. 8, a side semi-sectional view taken along line 8-8 ofFIG. 5 illustrates the integral connectivity of circular protrusion 81with the upper angled curved portion 71. Seen for the first time inisolation are a pair of pin apertures 107 for engaging the locking pin87.

Referring to FIG. 9, an illustration of a side plan view and in whichthe lower tube curved portions 65 and 69 are in matching straightalignment and forming a lower tube shape, while the upper angled curvedportions 67 and 71 are angled apart.

Referring to FIG. 10, a midpoint of movement is illustrates wherein thelower tube curved portions 65 and 69 have begun to move apart wideningthe lower tube shape previously formed into an angled apart opposingcurved shape, while the upper angled curved portions 67 and 71 arebrought closer together to have a closer though angled apart an angledapart opposing curved shape.

Referring to FIG. 11, a completed movement, with respect to the view ofFIG. 4 illustrates a state where the lower tube curved portions 65 and69 have moved apart to their maximum extent into a maximally angledapart opposing curved shape, while the upper angled curved portions 67and 71 are brought completely together to form an upper tube shape. Itis the position of FIG. 6 which is the ideal working position once thelower tube curved portions 65 and 69 are within the body, and providesan expanded working field at the base of the working tube 35. Surgicalwork is ideally performed through the upper, abbreviated axial lengthtube shape formed by the upper angled curved portions 67 and 71.

Referring to FIG. 12, a side view of the obturator 33 of FIG. 1 is seenin an assembled view and emphasizing in dashed line format a throughbore 111 which extends though the obturator 33 from the knurled knob 50through to the tip of the pair of spreading legs 39 and 41 (leg 41 isnot seen in FIG. 12.

Referring to FIG. 13, a side view of the obturator 33 of FIG. 11 is seenin an assembled view but turned ninety degrees about its axis, and aginemphasizing in dashed line format the through bore 111 which extendsthough the obturator 33 from the knurled knob 50 through to the tip ofthe pair of spreading legs 39 and 41. It is from this position thatfurther actuation will be illustrated.

Referring to FIG. 14, a side view of the obturator 33 of FIG. 13 is seenbut with the spreading legs 39 and 41 in an angled apart relationship.An optional support 112 is supported by the upper control housing 37 toenable independent support and location of the obturator 33 should it beneeded. Once the knurled knob 50 is turned, the wedge 51 seen in FIG. 1is driven downward causing the spreading of the spreading legs 39 and41.

Referring to FIG. 15, a sectional view taken along line 14-14 of FIG. 12gives a sectional view from the same perspective seen in FIG. 14. Pivotblocks 59 are seen as having pivot bores 113 which enable the upperportions 53 to pivot with respect to the upper control housing 37 andwhich enable the downward movement of the wedge 51 to translate into aspreading of the spreading legs 39 and 41.

As can be seen, the knob 50 and control shaft 49 and the wedge 51 havethe through bore 111. In the configuration shown, the control shaft 49includes a threaded portion 114 which engaged an internally threadedportion 115 of an internal bore 117 of the upper control housing 37. Theboss 47 is shown to be part of a larger insert fitting within a largerfitted bore 119 within the upper control housing 37. This configurationpushes the wedge 51 downwardly against an internal wedge conformingspace 123 to cause the insertion tangs 55 and upper portions 53 tospread apart. The wedge conforming space 123 need not be completelywedge shaped itself, but should ideally have a surface whichcontinuously and evenly in terms of area engages the wedge 51 to giveeven control. Further, the wedge 51 can be configured to be rotatablewith or independently rotationally stable with respect to the controlshaft 49. As can be seen, the through bore 111 continues below theinternal wedge conforming space 123 as a pair of curved surfaces 125 inthe upper portion 53, as well as a pair of curved surfaces 127 in thepair of spreading legs 39 and 41.

Referring to FIG. 16 a view of obturator 33 similar to that of FIG. 15,but turned ninety degrees along its axis is seen. In this view, thewedge 51 is seen as having a narrower dimension to lend internalstability by narrowing the bearing area of the wedge 51 action inopening the pair of spreading legs 39 and 41.

Referring to FIG. 17, a closeup view of the external hinge assembly 77seen in FIG. 1 illustrates the optional use of a plug 131 to cover theexposed side of the circular protrusion 81.

Referring to FIG. 18, a view taken along line 18-18 of FIG. 11illustrates a view which facilitates the showing of an optional skirt,including a skirt section 133 welded or otherwise attached to lower tubecurved portion 65, and a skirt section 135 welded or otherwise attachedto lower tube curved portion 69. The skirts sections 133 and 135 aremade of thin flexible metal and interfit within a pair of accommodationslots 137 and 139, respectively.

Referring to FIG. 19, a view of the lower tube curved portions 65 and 69in a close relationship illustrates the manner in which the skirtssections 133 and 135 fit within the accommodation slots 137 and 139 whenthe lower tube curved portions 65 and 69 are brought together to acircular configuration.

Referring to FIG. 20, a cross sectional view of a patient 151 spine 153is shown for illustration of the general sequence of steps taken for anyprocedure utilizing the minimal incision maximal access system 31. Thereare several procedures utilizable with the minimal incision maximalaccess system 31. Only a first procedure will be discussed usingillustrative figures. Other procedures will be discussed after minorvariations on the minimal incision maximal access system 31 are givenbelow.

Procedure I: Diskectomy and Nerve Decompression

The patient 151 is placed prone on radiolucent operating table such as aJackson Table. The patient 151 is then prepared and draped. Theoperative area is prepared and localized and an imaging device isprepared. A guide pin 155 is insert through the patient's skin 157,preferably under fluoroscopic guidance. The insertion of guide pin 155into a patient determines a depth from a skin surface and establishes acorrect level of surgery of said patient to a facet joint of saidpatient;

In the alternative and or in combination, the patient 151 skin can beincised with a scalpel. Other features in FIG. 20 include the dural sac159, and ruptured intervertebral disc 161.

Referring to FIG. 21, a fascial incisor 169 over fits the guide pin 155and is further inserted to cut through external and internal tissue. Thefascial incisor 169 is then removed while the guide pin 155 is left inplace. Next, using the obturator 33, the surgeon clears the multifidusattachment with wig-wag motion of the obturator 33 tip end. Next theobturator 33 is actuated to gently spread the multifidus muscle, andthen closed.

Referring to FIG. 22, next the assembled Working Tube 35—Obturator 33 isinserted into the area previously occupied by the fascial incisor 169and advanced to the operative level lamina and remove the obturator 33.As an alternative, and upon having difficulty, the obturator 33 could beinitially inserted, followed by an overfit of the working tube 35. Inanother possibility, a smaller size of obturator 33 and working tube 35or combination thereof could be initially utilized, followed by largersizes of the same obturator 33 and working tube 35. The assembledWorking Tube 35—Obturator 33 in place is shown in FIG. 22 with theworking ends very near the spine. The working tube 35 may be held orstabilized in the field of view by a support 181 which may have anengagement sleeve 183 which fits onto the working tube.

Referring to FIG. 23, the obturator 33 is actuated to a spreadorientation, which automatically actuates the working tube 35 to aspread orientation. Spread is had to the desired exposure size. Theobturator 33 is thin actuated to a closed or non-spreading position. Theobturator and working tube is then again advanced to dock on the spine.The working tube 35 is then fixed to assume an open position either byutilization of the locking pin 87 or other fixation device to cause theworking tube 35 to remain open. Then, once the working tube 35 is lockedinto an open position, the obturator 33 is actuated to a closed ornon-spread position and gently removed from the working tube 35.

Referring to FIG. 24, the working tube 35 is in place. The working tube35 may be secured by structure ultimately attached to an operatingtable. As can be seen, the operative field adjacent the spine area isexpended even though the incision area is limited. The deeper a givensize of working tube 35 is inserted, the smaller its entrance area.After the working tube 35 is stabilized, the surgeon will typicallyclear the remaining multifidus remnant at the working level and then setup and insert an endoscope or use operating microscope or loupes. Thesurgeon is now ready to proceed with laminotomy.

Referring to FIG. 25, further detail on the support 181 and engagementsleeve 183 is shown. A base support 185 may support a ball joint 187,which may in turn support the support 181. The support 181 is shown assupporting a variation on the engagement sleeve 183 as a pivot pointsupport engagement end 188 having arm supports 189 and 191. The armsupports 189 and 191 engage the external pivot structure on the workingtube 35 which was shown, for example, in FIG. 1 to be the external hingeassembly 77.

As a further possibility, the upper angled curved portions 67 and 71 areshown as being engaged about their outer periphery by an adjustableclamp 195. Adjustable clamp 195 includes a band 197 encircling the upperangled curved portions 67 and 71. The ends of band 197 form a pair ofopposing plates 199 and are engaged by a nut 201 and bolt 203 assembly.

Referring to FIG. 26, a side view of the assembly seen in FIG. 25 isseen with the adjustable clamp 195 operable to hold the working tube 35open at any position. Referring to FIG. 27, a top view looking down uponthe adjustable clamp 195 seen in FIGS. 25-27 shows the orientation ofthe working tube 35 and adjustable clamp 195 in fully closed position.When used in conjunction with the adjustable clamp 195, the Reinforcedwear plates 73 and 93 are eliminated so as to provide a smooth interfaceagainst the exterior of the upper angled curved portions 67 and 71.

Referring to FIG. 28, a variation on the obturator 33 is seen. Anobturator 215 has handles 217 and 219 which operate about a pivot point221. A working tube 222 is somewhat simplified but is equivalent to theworking tube 35 and is shown as including upper angled curved portions67 and 71. Handle 219 has a ratchet member 223 extending from it and alatch 227 pivotally connected about pivot point 229 to handle 217.

Referring to FIG. 29, a variation on obturator 33 is seen as anobturator 241 having an upper housing 243, control shaft 245 having athreaded section 247 and operating through a ball nut 249. A wedge 251is extendable down through an operation space made up of a half space253 in a leg 255 and a half space 257 in a leg 259. Hinge structures 261are shown attaching the legs 255 and 259 to the upper housing 243. Athrough bore 111 is also seen as extending from the knob 261 through tothe bottom of the wedge 251. An access groove 263 is carried by the leg259 while An access groove 263 is carried by the leg 259 while an accessgroove 265 is carried by the leg 255.

Referring to FIG. 30, a sectional view taken along line 30-30 of FIG. 29illustrates the use of a central support block 271 to support the acentral threaded surface 273 and the legs 255 and 259.

Referring to FIG. 31, a view of a thin, inset hinge 281 utilizable withany of the obturators, but particularly obturators 33 and 241, is shown.In the case of obturator 33, by way of example, upper portions 53accommodate control shaft 49 with its through bore 111. Inset hinge 281may be have an inset 283 and secured with machine screws 285. Insethinge 281 may be made of a “living hinge” material such as a hardplastic, or it can have its operations base upon control bending of apre-specified length of steel, since the angle of bend is slight. Theconnection between the upper portions 53 and the upper control housing37 may be by any sort of interlocking mechanism, the aforementionedpivot blocks 59 or other mechanism.

Referring to FIG. 32, a sectional view of the obturator 33 within theworking tube 35 is seen. The wedge 51 is seen at the bottom of theinternal wedge conforming space 123. Once the spreading of the workingtube 35 is accomplished the working tube 35 is kept open by any of themethods disclosed herein. Also seen is a pivot ball 116 to allow thecontrol shaft 49 to turn with respect to the wedge. The pivot ball willcontinue to support a central aperture bore 111. Once the working tube35 is stabilized in its open position, the obturator 33 is returned toits collapsed state as is shown in FIG. 33.

Provision of electro-mechanical power to the operation of the workingtube 35 can provide a surgeon an additional degree of instant control.Referring to FIG. 34, a top and schematic view of the use of a remotepower control to provide instant control of the working tube 25, similarto the view seen in FIG. 25 illustrates the use of a remote annularcontrol cable 301 using an internal cable 303 which is closely attachedusing a guide 305 and which emerges from the guide 305 and circles theupper angled curved portions 67 and 71, terminating at an end fitting307.

The annular cable 301 is controlled by a BATTERY MOTOR BOX 311 having aforward and reverse switch 313 (with off or non actuation being themiddle position). This enables the surgeon to expand the surgical fieldas needed and to collapse the surgical field to focus on certain workingareas. BATTERY MOTOR BOX 311 is configured with gears to cause the cable303 to forcibly move axially within the annular cable 301 to transmitmechanical power to the working tube 35.

Referring to FIG. 35, a view taken along line 35-35 of FIG. 34illustrates how the cable 303 is held in place and a closeup of the endtermination 307.

Referring to FIG. 36, a mechanically operated version of the nut 201 andbolt 203 constriction band seen in FIG. 25. The mechanical power linkagecan be provided remotely as by a rotating annular cable, but the basicmechanical setup shown illustrates the mechanical principles. On thebolt 203, a gear head 325 is placed, either by attachment or by theprovision of a threaded member and gear head made together. A secondgear head 327 is utilized to show the possibility of providing a rightangle power take-off in the event that the power connection interfereswith the area around the surgical field. A shaft 329 extends from aBATTERY MOTOR BOX 331. The BATTERY MOTOR BOX 331 has a forward andreverse switch 333, (with off or non actuation being the middleposition). Shaft 329 could be flexible and connected directly into axialalignment with the threaded member of bolt 201 or an integrally formedthreaded member.

Advantages Over Existing Surgical Techniques

In terms of general advantages, there are differences between theminimal incision maximal access system 31, and its components asdescribed in all of the drawings herein (but which will be referredthroughout herein simply as the minimal incision maximal access system31, or simply system 31) and other devices and procedures.

1. With regard to the Traditional microdiskectomy technique, the minimalincision maximal access system 31 allows for at least the same, if notbetter visualization access of the operative field. System 31 offers thesame 3-Dimensional work ability or, if preferred, an endoscope can beutilized. System 31 minimizes muscle injury with spread versus extensivecautery dissection. System 31 has clear advantage on the challengingobese and very large patient where the traditional microdiskectomytechnique is almost impossible to be applied.2. With regard to open pedicle screw insertion procedures, system 31offers muscle approach minimizing muscle devascularization anddenervation. The traditional approach had required at least one levelproximal and one level distal additional exposure causing extensivemuscle injury often leading to “fibrotic” muscle changes resulting inchronic painful and stiff lower back syndrome. System 31 offers the mostdirect approach to the pedicle entry point selecting the avascular planebetween the longissimus and multifidus muscles.3. With regard to the Sextant Procedure, system 31 offers clearadvantage over the Sextant procedure. First, the system 31 offers aprocedure which is not a blind pedicle screw technique. System 31 can beapplied to larger and more obese patients in which the Sextant procedurecannot be utilized. In this procedure using system 31 oosterolateralfusion can be performed along with insertion of the pedicle screws. Thesextant procedure is strictly a tension band stabilization.

In general, the components of the minimal incision maximal access system31 are very simple the hemispherical shapes used for the working tubecan be round or oval or flat. A keying system can be had to align theobturator 33 to the working tube 35. In the case of an oval system, thealignment would be automatic.

The minimal incision maximal access system 31 is a modular system withinterchangeable parts for both the working tube 35 and the obturator 33.The guide Pin 155 is of simple construction, as is the fascial incisor169. The working tube 35 has a limited number of basic parts, and can bemade in the simple, two main piece version of FIG. 28, or themulti-piece version of FIG. 1, which enables retractor-sleevesubstitution. A hinge and stabilization mechanism completes thesimplified construction.

The obturator 33 is also of simple construction, with upper controlhousing 37, pair of spreading legs 39 and 41, and an internal hinge,whether the pivot blocks 59 or hinge 281 and its ability to support acontrol shaft 49 having a bore 111 for a guide pin 155. Guide pin 155may preferably have a size of from about 0.3 mm to 0.40 mm diameter and30 cm to 40 cm in length. The fascial incisor may preferably becannulated for usage with the guide pin 155 and have a width of about 2mm more than the associated retractor. The overall cutting head lengthof about 1.2 cm has a shape as indicated in the Figures and has athickness slightly larger than that of the guide pin 155.

The working tube 35 can have several variations and added detailsincluding the simplest shapes as dictated by intended usage. Workingtube 35 can have a simple fluted hemi-tube shape or a Slanted box shape.Further, the possibility of a fluted oval shape is dictated when theapproach is more angular. The working tube 35 can have an attachment foran endoscope. Working tube 35 can also have a non-symmetric appearanceas by having longitudinal cross sectional shape with half of its shapebeing rounded and one half of its shape being rectangular or box shaped.This could also give rise to a similarly shaped obturator 33. Theworking tube 35 should have an anti-reflective inner coating and may beof modular construction.

The preferred lower dimensions for the lower tube curved portions 65 and69 include an overall shape which is semi tubular round or oval andhaving a width of from about 1.6-3.0 cm and a length of from about4.0-18 cm. Curved portions 65 and 69 may have custom cut outs dependingupon planned application.

The hinge assembly 77 may have male-female post or male-female dial lockdesign, as well as a hinge housing and a bias (by spring or othermechanism) to keep angular displaceable portions of the working tube 35closed. a “universal” port provides a point of attachment of anendoscopic or stabilizer bar.

The obturator 33 may be any controlled opening device including acircular band or cable, force Plates, or a device attached to hingeassembly 77 or other hinge assembly.

All sleeve attachments including the attachable legs 39 and 41, as wellas the lower tube curved portions 65 and 69 should be of the frictiongrip type or snap and lock type or other suitable connection method orstructure.

Obturator 215 may have squeeze grip scissor style handles 219 and 217and a controlled dilator. It may utilize an enclosed design with ahandle cover having a no-slip surface. It may be attached to the hingehousing of the working tube or separate hinge housing. In fact, it maybe of a design to be held in place solely by the working tube 35.Ideally a cavity will be provided through the center axis to contain theshaft for the dilator mechanism if applicable.

The central bore 111 of the obturator 33 may have a diameter of fromabout 5-10 mm, depending upon the size of the obturator 33 utilized.Obturator 33 should be provided in various widths and length to matchworking tube. The working tips of the spreading legs 39 and 41 may bechangeable according to surgical procedures as described in theoperative procedures herein. It may have an inner chamber, or internalwedge conforming space 123 slanted in shape wider proximal and morenarrow distal to accommodate the wedge 51. The internal wedge conformingspace 123 can be enclosed with expanding, contracting sleeve.

Other Procedures

Many other procedures can be facilitated with the use of the inventiveminimal incision maximal access system 31 and methods practicedtherewith. Procedure I, a diskectomy and nerve decompression procedurewas described above with reference to the Figures. Other procedures areas follows:

Procedure II: Facet Fusion

1. Patient prone on Jackson Table with normal lordosis preserved. Thiscan be increased by placing additional thigh and chest support toincrease lumbar lordosis.

2. Insert percutaneous special guide pin perpendicular to the floor at apoint 1 cm caudal to the Alar-Superior facet notch for determining depthfrom a skin surface and to establish a correct level of surgery of saidpatient to a facet joint of said patient.

3. Apply a flag guide to a first guide pin 155 #1.

4. Measure skin to bone depth from the scale on guide pin 155 #1.

5. Slide drill guide mechanism on the flag guide to match the skin bonedistance.

6. Insert guide pin 155 #2 through the drill guide to dock on thesuperior facet.

7. Make a small skin incision for the obturator 33.

8. Working tube 35 should be small oval or round with medial cutout tomaximally medialize the working tube 35.

9. Advance the working tube 35 to the L5-S1 joint and dock.

10. Drill the guide pin across the joint medial to lateral, rostral tocaudal. If in proper position, advance across the joint to engage theala.

11. Drill across the joint with a cannulated drill.

12. Check depth flouroscopically and measure.

13. Pick appropriate screw length.

14. Insert specially designed facet screw and protective bracket, securetightly.

Procedure III: Posterior Lumbar Interbody Fusion (PLIF)

1. First half of the procedure similar to microdiskectomy (Procedure I)except for the use of a larger diameter sized working tube 35. Use a20-25 mm round or elliptical diameter working tube 35 with a medialcutout to allow docking as close to midline as possible.

2. Following diskectomy enlarge the laminotomy to accommodate the toolsuse for the specific PLIF such as Brantigan cage or Tangent.

Procedure IV: Transfacet Interbody Fusion (TFIF)

1. Follow the same procedure as the PLIF in terms of selecting andinserting the Working Tube 35.

2. Following the diskectomy, resect the facet joint.

3. Approach the posterolateral disc space through the medial ⅔ of thefacet joint. Take care not to injure the exiting root above.

4. Proceed with Brantigan cage instruments and interbody cages.

Procedure V: Pedicle Screw Instrumentation Technique

1. Place the patient 151 Prone position on a Jackson Table.

2. Guide pin 155 is docked on facet joint angled 30 degree lateral tomedial in the plane between the longissimus muscle longitudinally andmultifidus muscle medially.

3. Make skin incision.

4. Fascial incisor introduction.

5. Introduce the obturator 33 working tube 35 assembly between thelongissimus and multifidus and progressively open the obturator 33 tipends of the legs 39 and 41, gradually reaching from the joint above andthe joint below.

6. Advance the working tube 35 and retract the obturator 33.

7. Use the elliptical Working Tube size 2.5 cm wide and open up to 5 cm.

Procedure IV: Anterior Lateral Lumbar Diskectomy Fusion

1. Mid lateral decubitus position left side up. Place a “waist roll” toprevent sag of the mid lumbar spine.

2. Identify proper level of surgery fluoroscopically.

3. Insert a guide pin 155 #1 percutaneously into the superior facetperpendicular to the spine.

4. Measure depth skin to joint on the scaled guide pin 155 #1.

5. Insert cannulated flag guide over guide pin 155 #1.

6. Slide the drill guide to match the depth.

7. Insert a guide pin 155 #2 down to the disc space.

8. Make skin incision and insert fascial cover.

9. Insert the working tube 35 and Obturator 33 combination.

10. Progressively dilate the obturator 33.

11. Advance the working tube 35.

12. Perform anterolateral diskectomy and interbody fusion as taughtabove.

13. Use a round or oval shaped retractor or lower tube curved portion 65and 69 as inserts preferably with distal end cutouts in each.

Procedure VII: Posterior Cervical Foramenotomy and Lateral Mass Plating

1. The patient is placed in a prone position on a Jackson table.

2. Fluoroscopic identification of the level of surgery is had.

3. Percutaneously insert guide pin 155 with AP and lateral fluoroscopicviews.

4. Make the initial skin incision.

5. Apply the working tube 35 with obturator 33 into the incision.

6. Perform slow dilation of the muscle.

7. Advance the working tube 35 and collapse and remove the obturator 33.

8. Proceed with surgery. Type of sleeve or lower tube curved portion 65should be round or oval with slanted and to match the slanted lamina.

9. For application for Lateral mass plating use an oval working tube 35for a greater exposure.

Procedure VIII: Anterior Cervical Diskectomy Fusion

1. Begin with standard anterior cervical diskectomy fusion approach witha incision on the left or right side of the neck.

2. Blunt finger dissection is performed between the lateral vascularstructures and the medial strap muscle and visceral structures down tothe prevertebral fascia.

3. Establish the correct level to be operated on fluoroscopically andthe guide pin 155 inserted into the disc.

4. Apply the working tube 35 and obturator 33 combination and dock atthe proper level of the anterior spring.

5. Open the working tube 35 and obturator 33.

6. Mobilize longus colli muscle.

7. Use special Bent Homen Retractor specifically design to retract thelongus colli.

8. Proceed with surgery.

Procedure IX: Anterior Lumbar Interbody Fusion

1. Begin with the standard approach whether it is retroperitoneal,transperitoneal or laparoscopic.

2. Apply the special anterior lumbar interbody fusion working tube 35and obturator 33. This is a design with a medial lateral opening. It isoval shape and preferably with skirts 133 and 135. The distal end of theretractor blade is slightly flared outward to retract the vesselssafely. There is a skirt 133 or 135 applied to the cephalad side andpossibly to the caudal side.

3. With the vessels and the abdominal contents safely retracted out ofharms way, proceed with diskectomy and fusion.

One of the aspects emphasized up to this point for the system 31 isstructure and circumstance to minimize the upper entry point of thesurgery while providing an expanded working area at the distal end ofthe tube. Structures which achieve this geometry have been shown, andinclude a flared upper end so that the aperture remains open regardlessof the angle of spread.

In other applications it is permissible to expand the aperture openingat the top of the working sleeve assembly. Expansion can be for thepurposes of introducing further working devices into the working tube,as well as to expand and protect the visual field. For example, furtherworking devices may include implant tools and their held implants, toolsto insert plates and screws, and tools to manipulate all of these intotheir final positions.

Visual field protection can be introduced where the surrounding tissuemay tend to flow, move or obstruct the surgical working field. Where thebottom-most portions of the spread apart curved tube are spread apart,tissue tends to enter the space between the bottom parts of the tube.Additional guarding structure needs to be introduced.

A description of the desired articulation of what is hereinafterreferred to as a working tube assembly 417, and including the workingtube curved portions is begun with respect to FIG. 37. The designationof working tube assembly 417 refers to all of the tube structures seenin the earlier FIGS. 1-36 and as seen in any of the following Figures.

FIG. 37 is an isolated view of two curved tube sections shown joined ina tubular relationship and indicating at least a pair of pivot axes oneach curved tube section.

At the top of the structure shown in FIG. 37 a dashed line indicates anoptional fluted structure 419. Fluted structure is omitted from thedrawings for FIGS. 37-49 in order that the views from the top will notbe obscured. The optional fluted opening 419 and is often employed bothto maintain the visual field upon opening, as well as to make it easierto add instrumentation into the surgical field. This structure isrecommended, as well as all reasonable accommodation to facilitate itsuse.

a first curved tube 421 is shown in alignment with a second curved tube423. Rather than having the upper ends flared out to maintain a circularvisual field on a full open position, a clearance notch 425 is providedin first curved tube 421, while a clearance notch 427 is provided insecond curved tube 423.

The lowermost extent of the clearance notches 425 and 427 coincide withan upper pivot axis 431 of first curved tube 421 and upper pivot axis433 of first curved tube 421. The pivot axes 431 and 433 may includesupports either derived from structures going into or out of the firstand second curved tubes 421 and 423. In the view of FIGS. 37-39, thestructures seen facing the viewer are repeated on the opposite side.Thus, pivot axes 431 and 433 are also located on the side opposite thatseen in FIGS. 37-39. The same is true for all of the numberedstructures. In this position, the simultaneous pivoting about the pivotaxes 431 and 433 of the first and second curved tubes 421 and 423 willnot cause interference by portions of the first and second curved tubes421 and 423 which would otherwise interfere.

Further, a lower pivot axis 435 is provided below the upper pivot axis431 of first curved tube 421. Similarly, a lower pivot axis 437 isprovided below the upper pivot axis 433 of second curved tube 423. Pivotaxes 441, 433, 435 and 437 may also be expected to translate. Thegeometry and pivot points having been identified, double headed arrowsillustrate that the pivot points should be able to move toward and awayfrom each other. Ideally, the only limitation should be the interferencefrom the lower ends of the first and second curved tubes 421 and 423with each other. Where the mechanism for moving the first and secondcurved tubes 421 and 423 has maximum independence, secondaryconsiderations of interference are eliminated and only the primaryinterference between the first and second curved tubes 421 and 423 willremain. Where the control mechanism for movement is lesser than thatwhich allows maximum independence, savings can be had in terms ofcomplexity of the mechanism at the expense of the freedom of movement.

FIG. 37 illustrates the first and second curved tubes 421 and 423 in aclosely aligned relationship where the upper pivot axis 431 is closestto the upper pivot axis 433 and where the lower pivot axis 435 isclosest to the lower pivot axis 437. This is the position expected to beused for entry into the body of the patient, especially along with aguide (to be shown) which will be located within and extending below theassembled and parallel linear tube formed by first and second curvedtubes 421 and 423 to provide a reduced insertion resistance.

Ideally, the first and second curved tubes 421 and 423 will be insertedas shown in FIG. 37 and then manipulated to a position shown in FIG. 38.FIG. 38 is an isolated view of two curved tube sections as seen in FIG.38 which are angularly displaced apart about a shared first pivot axison each of the curved tube sections. The position in FIG. 38 ischaracterized by the fact that upper pivot axes 431 and 433 have thesame separation as seen in FIG. 37, but in which the lower pivot axes435 and 437 have moved apart. The position seen in FIG. 38 will belikely achieved just after insertion and in which the internal tissueshave been pushed apart. Depending upon the surgical procedure, the firstand second curved tubes 421 and 423 will be chosen based upon length, sothat the lower end will be at the correct height for the tissues to beviewed, manipulated and treated. The action can continue until the lowerends of the first and second curved tubes 421 and 423 are sufficientlyspaced apart for view and manipulation of the tissues between andadjacent the lower ends. If there is a sufficient viewing opening basedupon the original distance of separation of the upper pivot axes 431 and433, the procedure may continue through an aperture about the same sizeof the tube shape seen in FIG. 37.

Where more of an opening is needed, the first and second curved tubes421 and 423 upper pivot axes 431 and 433 can move more widely apartuntil a position such as that seen in FIG. 39 is achieved. FIG. 39 is anisolated view of the two first and second curved tubes 421 and 423 whichare angularly displaced apart about a shared second pivot axis on eachof the curved tube sections. It should be emphasized that the positionseen in FIG. 39 is a position where both the first and second curvedtubes 421 and 423 are parallel and separated from each other, but thisneed not be the case. From the position seen in FIG. 38, the upper pivotaxes 431 and 433 can be moved apart from each other while the lowerpivot axes 435 and 437 either remain a constant distance from each otheror are brought together. This range of articulation described can beused to physically manipulates the tissues in contact with the first andsecond curved tubes 421 and 423 for any number of reasons, includingintroduction of further instruments if necessary, as well as to react tochanging conditions of tissue at the lower tube.

In both FIGS. 38 and 39 a pair of opposing edges 439 can be utilized tosupport structures introduced between the first and second curved tubes421 and 423. Other structures can be used including depressions,apertures and internal projections, such as hooks or latches. Aninternal structure within the first and second curved tubes 421 and 423would pose little risk of nick to the patient and can be designed to donothing more than have a minimal interference effect with respect to thevisual field.

As will be shown, a number of external structures can be employed toachieve the relative separation positions of the upper pivot axes 431and 433, as well as the lower pivot axes 435 and 437 that nearly anytype of angle can exist on either side of a parallel relationshipbetween the first and second curved tubes 421 and 423, but that mostwill be in a range of from a parallel relationship to some form ofangular relationship seen in FIG. 38, where the upper ends at theclearance notches 425 and 427 are closer together than the lower endsdistal to the upper pivot axes 431 and 433 and lower pivot axes 435 and437.

One example of a side shield 441 is seen in FIG. 40. FIG. 40 is a planview of a given width supplemental side shield 441 having a width ofapproximately the separation of the curved tube sections as seen in FIG.39, while accompanying FIG. 41 is a top view of the supplemental sideshield 441 of FIG. 40 emphasizing its shape. The side shield 441 can beof any shape, but is shown in a rectangular shape to correspond with thefirst and second curved tubes 421 and 423 in a parallel position as seenin FIG. 39. The side shield 441 has a main portion which includes afirst side 443 and a pair of lateral engagement portions 445. The sideshield 441 can depend from a number of other structures, but the sideshield 441 seen in FIGS. 40 and 41 utilize an offset surfaces asengagement portions 445. This geometry, will, absent any interferingstructures which are attached to manipulate the first and second curvedtubes 421 and 423, enable the side shield 441 to be introduced linearlyfrom the top of first and second curved tubes 421 and 423. Theintroduction of side shield 441 may be guided somewhat into engagementby the clearance notches 425 and 427. Much smaller engagement portions445 could be used to engage the outer edges 439 of the first and secondcurved tubes 421 and 423, so long as the orientation is so as to protectthe surrounding tissues. FIG. 41 emphasizes the geometry and shows asecond side 447.

In the orientation shown, the second side 447 would face toward theinside of the general tube formed in the orientation of FIG. 39. If twoof the side shields 441 were used, one on either side of the openingseen in FIG. 39, the tube shape would be closed on both sides, and anoval viewing area would be formed. It should be emphasized that the sideshield 441 can depend from any structure, and not just the opposingedges 439 seen in FIG. 39. Structure used to manipulate the first andsecond curved tubes 421 and 423 can be used to both guide and secure anyside shield 443.

In terms of a structure to manipulate the first and second curved tubes421 and 423, it is preferable that the upper pivot axes 431 and 433 maybe urged toward and away from each other independently of the urging ofthe lower pivot axes 435 and 437 toward and away from each otherindependently. a mechanism which would prevent all manipulations of thefirst and second curved tubes 421 and 423 to a position of binding isdesirable, but its complexity may obstruct the surgical field. Forexample, it would be good to have a mechanism which would prevent upperpivot axes 431 and 433 from moving away from each other while the lowerpivot axes 425 and 437 are in their close proximity as depicted in FIG.37. In some cases operator knowledge and skill will probably berequired.

In terms of supporting the upper pivot axes 431 and 433 and lower pivotaxes 425 and 437, the pivoting and movement may be passive withmechanisms to push or pull directly on the first and second curved tubes421 and 423 or structures which are mechanically attached. As an exampleof the use of force and movement urging at the pivot points, FIG. 42illustrates one such system as a pivoting thread support system 551. Thegearing is shown as unduly expansive to illustrate simply the action,but in reality, several gears may be used.

Further, since the a pivoting thread support system 551 is viewed fromthe top, and as operating the upper pivot axes 431 and 433, a similararrangement would be used for the lower pivot axes 425 and 437. a set offour pivot fittings 553 provide a threaded interior spaced apart fromthe first and second curved tubes 421 and 423, or fittings supportingthe first and second curved tubes 421 and 423. The fittings 553 enablethe first and second curved tubes 421 and 423 to tilt while keeping thethreaded apertures in alignment.

a first threaded member 555 has a pair of threaded areas in which thethreads are oppose pitched. The threads engaging the fitting 553 offirst curved tube 421 are set to urge first curved tube 421 away fromsecond curved tube 423, at the same time that the same turning of thefirst threaded member engages fitting 553 of first curved tube 423 setto urge first curved tube 423 away from second curved tube 421. Thismeans that the turning of first threaded member 555 in one directionurges the first and second curved tubes 421 and 423 evenly away fromeach other, and alternatively, the turning of first threaded member 555in the opposite direction urges the first and second curved tubes 421and 423 evenly toward each other.

Likewise, a second threaded member 557 has a pair of threaded areas inwhich the threads are oppose pitched. The threads engaging the fitting553 of first curved tube 421 are set to urge first curved tube 421 awayfrom second curved tube 423, at the same time that the same turning ofthe first threaded member engages fitting 553 of first curved tube 423set to urge first curved tube 423 away from second curved tube 421, butin an oppose orientation than the threads of first threaded member 555.This means that the turning of second threaded member 557 in the otherdirection (while the first threaded member 555 is turned in a firstdirection) urges the first and second curved tubes 421 and 423 evenlyaway from each other. a pair of over sized gears, including a first gear559 associated with the first threaded member 555, and a second gear 561associated with the second threaded member 557 act to cause the firstand second threaded members 555 and 557 to move simultaneously andoppositely. a knob 563 is used to manipulate both the first gear 559,which manipulates the second gear 561. In a realization in which moregears 559 and 561 are provided, the size of the gears can be reduced andfor each intermediate gear, the sense of the threaded members 555 and557 will change from opposite to same.

Referring to FIGS. 43 and 44, a surrounding frame system 571 is seenwhich is utilized to provide and enable pivoting and translation. Asurrounding frame 573 has an open slot 575 which accommodates a pair ofpins 577 and 579 which preferably have some tracking along the slot 575to insure that neither the first curved tube 421 nor the second curvedtube 423 are able to turn within the frame 573. The opposite side of theframe 573 will have a similar slot 575. However, where the structureswhich engage the slot are especially over sized, or where the structuralintegrity is sufficient, only one slot need be used. The structuraldependence on the frame 573 should be such that the two opposing firstand second curved tubes 421 and 423 will always oppose each other andcannot twist away from each other and can only pivot along their longaxis.

a turn fitting 581 enables a threaded member 583 to turn while beingaxially fixed to the first curved tube 421. The threaded member 583 maybe threadably engaged to an internal thread 585 at the end of the frame573. In this case a knob 587 is used to manually turn the threadedmember 583 independently to move the first curved tube 421 to the leftor to the right. A turn fitting is a structure which holds the end ofthe threaded member and allows the threaded member 583 to urge thefitting forward or backward while continuing to turn.

In the alternative, knob 587 may have an internal thread, and turnedwith respect to the threaded member 583 draw the threaded member out ofthe frame 573. In this case, a spring (as will be shown) could be usedto help reverse this operation. Where the knob 587 is internallythreaded, the end of the threaded member may be fixed directly to itsfirst curved tube 421.

In sum, there are three ways to affect motion, preferably the internalthreads 585 enable the threaded member 583 to turn to urge first curvedtube 421 in both directions with respect to the frame 573. In thealternative, the threaded member 583 may act only to urge the firstcurved tube 421, and the tubes 421 and 423 may have another mechanismurging them apart or simply move apart based upon other forces or otherstructures present. Third, the threaded member 583 may have an endanchored to the first curved tube 421 with an internally threadedsurface inside knob 587 to enable the knob 587 to be turned to cause thelength of threaded member 583 to be withdrawn from the frame 583. Aspring, or other fitting can be used to help reverse the direction oftravel. All of the knobs and threaded members shown hereafter have theability for all three modes of action.

Similarly, a turn fitting 591 enables a threaded member 593 to turnwhile being axially fixed to the second curved tube 423. The threadedmember 593 threadably engaged to an internal thread 595 at the end ofthe frame 573. a knob 597 is used to manually turn the threaded member593 independently to move the second curved tube 423 to the left or tothe right.

Similarly, a second surrounding frame 573 has an open slot 575 whichaccommodates a pair of pins 601 and 603 having expanded heads which fitoutside the slot 575 to provide tracking along the slot 575 to furtherinsure that neither the first curved tube 421 nor the second curved tube423 are able to turn within either of the frames 573.

a turn fitting 611 enables a threaded member 613 to turn while beingaxially fixed to the first curved tube 421. The threaded member 613 isthreadably engaged to an internal thread 615 at the end of the frame573. a knob 617 is used to manually turn the threaded member 613independently to move the first curved tube 421, at its lower pivot axis435 at the center of the pin 601. Similarly, a turn fitting 621 enablesa threaded member 623 to turn while being axially fixed to the secondcurved tube 423. The threaded member 623 threadably engaged to aninternal thread 625 at the end of the lower located frame 573. a knob627 is used to manually turn the threaded member 623 independently tomove the second curved tube 423 to the left or to the right at its lowerpivot axis 437 at the center of the pin 603.

With the configuration of FIG. 43, the position within the upper locatedframe 573 and separation of the pivot axes 431 and 433 (represented bythe pins 577 and 589) can be exactly specified. Likewise, the positionwithin the lower located frame 573 and separation of the pivot axes 435and 437 (represented by the pins 601 and 603) can be exactly specified.In typical use, the knobs 617 and 627 and will be activated afterinsertion to achieve the configuration seen in FIG. 38, and thenfollowed by the use of the knobs 587 and 597 to achieve theconfiguration seen in FIG. 39, if necessary. Thereupon the optional sideshield 441 may be employed. Where a lesser separation than that seen inFIG. 39 is used, a narrower side shield 441 may be employed. In asurgical kit, several such shields 441 of different size and shape maybe available.

Referring to FIG. 44, a view looking down into the structure of FIG. 43shows the overall orientation and further illustrates an optionalsecuring tang 629 which may be used with either of the upper located orlower located frame 573, and may be located in any position, or extendedin any direction, to better enable the surgeon to stabilize andmanipulate any of the assemblies 417, 551 and 571 seen. Any structurecan be used to help secure the frame 573 and or the first and secondcurved tubes 421 and 423. FIG. 44 is an equivalent view through thelower of the frames 573, including the knobs 617 and 627 as the twoframes 573 have equivalent action. Note that having complete controlover both the separation, angular relationship, and position of thefirst and second curved tubes 421 and 423 within the frame 573 willenable the surgical practitioner to position the line of sight of theworking tube along the frame 573 length and to generally have completecontrol.

Also shown in FIG. 44 is an optional spring 630 which can be used tobias the force acting upon either of the first and second curved tubes421 and 423, or it can be used to bias a knob 597 away from the frame573. Although shown as an option, the use of a spring 639 may contributesignificantly where force is to be had in one direction only, as well asto lock a threaded member such as 593 into a turn fitting by keeping apulling bias in place.

In some cases it may be desired to reduce the number of controls toaccomplish certain objectives, such as simplicity, less controllability,less moving parts, inexpense, or the critical need for space about theupper part of any of the assemblies 417, 551 and 571. One example of anarrangement is seen in FIG. 45. a frame 631 has an interior having onesurface which may generally match one of the first and second curvedtubes 421 and 423, and in this case first curved tube 421. The frame 631may be attached to the first curved tube 421 by tack welding or thelike, or other means. A single threaded member 633 includes a knob 635.a structure 637 can be either an engagement turning block to enable thethreaded member 633 to both push and pull on the second curved tube 423,or it may simply be a wear block to allow the threaded member 633 topush against it and to protect the second curved tube 423 from wear.

Because half of the tube assembly of first and second curved tubes 421and 423 is supported by the frame 631, the second curved tube 423 isleft to move only slightly and assuming that FIG. 45 is an upper viewand that the pivoting of the second curved tube 423 is accomplished at alower level, especially at the level of lower pivot axis 437, the frame631 is left to control second curved tube 423 by simply pushing, or bypushing and pulling. Where structure 637 is a turning block, there is abulbous expansion at the end of threaded member 633 which snaps intostructure 637 as a turning block and is free to turn and both push andpull second curved tube 423. The threaded member 633 is threadablyengaged into an internal threaded bore 639 within the frame 631.

Referring to FIG. 46, one embodiment of a manipulative structure whichworks well with the structure of FIG. 45 is shown. The structure shownis a partial section taken at the lower pivot axis level and includesmeans for pushing and pulling, or pushing alone. Preferably, when usedwith the structure of FIG. 45, it will include pushing and pulling,especially if the structure of FIG. 45 performs pushing alone. Either ofthe structures in FIG. 43 at either the upper or lower pivot axis levelscan be substituted for either of the structures shown in FIGS. 45 and 46as the structures in FIG. 43 provide both pushing, pulling, pivoting andlevel support.

Where the structures of FIG. 45 provides both pushing and pulling, itcan be used along with a second structures at the lower pivot axis asany structure which provides both pushing and pulling will also providesome pivoting support. Further, the structure shown in FIG. 46 is hingedto provide additional pivoting support. The structure of FIG. 46 can beused at either the upper pivot axes 431 and 433 or the lower pivot axes435 and 437. Both the structures of FIGS. 45 and 46 demonstrate clearlythat lesser control structures than are shown in FIG. 43 can be used tocontrol the first and second curved tubes 421 and 423, along with lessercontrol inputs, and less control specificity, but also with less movingparts and a lesser mechanical complexity.

Referring again to FIG. 46, second curved tube 423 is seen as tackwelded to a reinforcement 651. The purpose of reinforcement 651 is toprovide an expanded thickness of material so that pivoting can occurcloser to the opposing edge 439 as is possible. It is further possibleto continue the extent of the reinforcement 651 and its pivot point inthe direction of first curved tube 421 if the other geometries of theother components permit. Reinforcement 651 contains a pair of threadedbores 653, each of which accommodates one of the threaded screws orbolts 655 shown. The bolts 655 each extend through one end of a “U”shaped fitting 657, so that the reinforcement 651 and attached secondcurved tube 423 pivots with respect to the fitting 657. a threadedmember 659 engaged an internal threaded bore 671, and has a knob 673 forease of manual operation.

The threaded member is connected to a turn fitting 675 the first curvedtubes 421 to be moved toward and away from second curved tube 423. Theuse of the structure of FIGS. 45 and 46 may be used together to give theability to provide control, although not as much control as is seen inFIG. 43.

Referring to FIG. 47, another possible realization is seen, combiningthe control mechanisms of selected portions of FIGS. 37-46, combinedwith other possible options. An open frame system 691 is seen as havinga frame 693 which is either open on at least one side, or which has aside expanded to a distance sufficient to introduce other structures toexpand in that direction. Some of the components previously seen includepins 577 and 579 extending through slot 575. Pins 577 and 579 may haveextended vertical and horizontal extent to garner additional stabilityfrom the frame 693, especially where one side is open.

Other structures may be used to insure that neither the first curvedtube 421 nor the second curved tube 423 are able to turn within theframe 573. Also seen are turn fitting 581, threaded member 583, knob587, turn fitting 591, threaded member 593, and knob 597. The view ofFIG. 47 is from above, and thus the structures most closely correspondto the upper structures seen in FIG. 43 and in FIG. 44.

As can be seen in FIG. 47, a four point retractor system can be formedwith the components and structures of the foregoing Figures. The firstand second curved tubes 421 and 423 are shown in the open position. Onthe longer connector arm of the frame 693, a side shield 695 issupported. The side shield 695 can derive its ability to hold tissue outof the visual field by being locked down onto the frame 693 in the samemanner as a wrench fits a bolt head. In this configuration, the sideshield can be inserted into the center of the surgical field and thenrotated into position and moved down slightly to lock it into place. Onthe opposite side from side shield 695 is a retractor 697 which has aflat portion entering the surgical field and which is controlled from apoint remote with respect to open frame system 691. An angled portion699 turns from the flat portion seen entering the surgical field andextends down into the area between the open first and second curvedtubes 421 and 423.

Also seen are a series of small circular structures 701 about theperipheral upper surface of first and second curved tubes 421 and 423.These structures are at least one of embedded fiber optics and ports foraccepting fiber optics. The apertures formed in the metal open at aslight angle to the inside of the first and second curved tubes 421 and423 to direct light into the surgical field without producing a backreflection or other scatter. In cases where the fiber optic ispermanently affixed, a light ring section can simply be snapped to orplaced on the first and second curved tubes 421 and 423. In cases wherethe apertures are provided, surgery can continue without fiber optics,or a fiber optics set can be added which can range from an illuminatedring (relying on low angle of incidence and Snell's law) to direct lightthrough the openings which open to the inside of the first and secondcurved tubes 421 and 423 at a low angle of incidence. Intermediarysolutions, such as a light ring having a series of short fiber opticmembers for insertion into the apertures can be used. To facilitate theuse of fiber optics, the curved tubes 421 and 423 may be made from acomposite material in which the fiber optic components may be presentduring formation of the tube structures. Other material may be used fortubes 421 and 423, including materials that either transmit light orhave portions which transmit light.

As an alternative to the three sided frame 693, the open portion of theframe could be enclosed by an expandable member 703 which can have anymanner of interlock with the three sided frame 693. One such interlockis illustrated as simply an annular piston dependence where theexpandable member 703 includes a smaller tubular insert 705 which fitsclosely into a matching bore 707 seen in the terminal ends of the threesided frame 693. The expandable member 703 can be used to lendadditional support to the three sided frame 693, especially forcesproduced by the threaded members 583 and 593. The expandable member 703is also useful to help support the retractor 697 where such provision ismade. The main purpose of expandable member 703 is the adjustability togive greater clearance and access. The same adjustability could be hadon the side of three sided frame 693 which supports side shield 695,especially with a more complex mechanism to enable the frame expansionto be locked into place. A locking mechanism for expandable member 703is not shown so that the drawings may be simplified, but lock abilitycan be achieved in the same manner as any metal to metal frameconstruction known in any field of art.

Referring to FIG. 48, a side view of the side shield 695 is seen. Theclearance for locking onto the frame 693 is about the same as the widthof the frame 693 so that non rotational fixation can be transmittedalong the length of the side shield 695.

Referring to FIG. 49, one possible configuration is seen for a variabledepth guide 711 which is utilizable with any of the devices seen inFIGS. 37-46 or any other tubular, minimally invasive system. Variabledepth guide 711 has a handle 713 controlling a shaft 715. Shaft 715 hasa through bore 717 which is used to insert a guide line or guide pin tohelp insert any minimal access system seen in the earlier Figures.

A translatable detent ring 719 interacts with a series of detentindentations 721. The position of the detent ring 719 will correspond tothe lengths of the first and second curved tubes 421 and 423 with whichthe variable depth guide 711 is used. Once the practitioner inserts thevariable depth guide 711 into any assembly containing a first and secondcurved tubes 421 and 423, the necessary height can be adjusted so thatthe tip of the variable depth guide 711 extends just beyond the lowerextent of the joined first and second curved tubes 421 and 423. Theheight is adjusted by forcing the detent ring 719 to the proper detentindentation 721, and then inserting it into a closely associated firstand second curved tubes 421 and 423 to form an overall bullet shape forinsertion, preferably a guide pin 155. Once inserted, the variable depthguide 711 is removed. The detent ring 719 carries a frusto-conicalsurface 723 where it is used with first and second curved tubes 421 and423 having fluted top areas as seen in FIG. 37 and in previous figures.Any mechanism can be used to achieve a detent action, including aninternal pressure ring or a spring loaded bar, or protruding ballbearings. The positional stability of the detent ring can be specifiedby the spring action of the detent member, and should be sufficientlystable to enable deliberate manual fixation with no inadvertent movementoccurring even where significant resistance is encountered.

Referring to FIG. 50 is a vertical plan view looking down upon anexpandable frame system 751 which uses detents to set the frame size andwhich uses an angular distribution system. A frame is used as a supportand reference point to manipulate a working tube in much the same way asFIGS. 37-47. Expandable frame system 751 enables the user to control thesize of the operating theater as needed. Where the task can beaccomplished with minimum opening access, such minimum opening is allthat needs to be taken. Where greater access is needed, the expandableframe system 751 provides both an expanded work space, and additionalsurfaces for support of other instrumentation.

As before, the retractor blades are seen as a first curved tube 753having an upper flared portion 755 and a second curved tube 757 havingan upper flared portion 759. Each of the first and second curved tubes753 and 757 have two points of variable pivoting attachment.

Curved tube 753 has a pivot bar 781 which may be attached somewhattangentially to the first curved tube 753, or may include a pair ofextensions attached to the outside of the first curved tube 753.Likewise, curved tube 757 has a pivot bar 783 which may be also attachedsomewhat tangentially to the first curved tube 753 in the same manner.

Pivot bar 781 has circular lands 785 which fit into support fittings787. Likewise pivot bar 783 also has circular lands 785 which fit intosupport fittings 787. The support fittings 787, as seen from above, showthe lands 785. In this configuration the lands 785 can be dropped infrom above. This is an over-simplified illustration, as some otherlocking mechanism can be utilized, including ball shape instead of discshape or other. It would be preferable that the manner of pivotingengagement will firstly enable an ease of assembly and disassembly andsecondly provide good stability against dislodgement with respect to anyforces experienced when the expandable frame system 751 is in anoperational position.

Above the point of pivot of the pivot bars 781 and 783, each of thefirst and second curved tubes 753 and 757 are fitted with a pivotbearing fitting 791. The pivot bearing fittings 791 can depend fromeither the first and second curved tubes 753 and 757 or their upperflared portions 755 and 759. The pivot bearing fittings 791 can be hingetype of ball type, or any other type which will enable the upper part ofthe first and second curved tubes 753 and 757 tp be force moved to pivotthem with respect to the pivot fittings 781 and 783 in either direction.

The pivot bearing fitting 791 is engaged by a cooperating fitting 793which enables the pivot bearing fitting 791 to pivot with respect to thecooperating fitting 793. The cooperating fitting 793 is moved with athreaded member 795, having a thumb control wheel as a tilt screw knob797. In the drawings of FIGS. 50 and 51, the fittings 791 are locatedabove the pivot bars 781 and 783, but they need not be.

In the embodiments of FIGS. 50 and 51 the movement of the axes of thepivot bars 783 are affected by the expansion of a frame supportincluding a first lateral member 801 and a second lateral frame member803. The ends of firs and second lateral members 801 and 803 areconnected to two telescoping frame members 805 and 807. Telescopingframe member 805 has a central hinge box 811 which is positioned betweena first sleeve 813 and a second sleeve 817. The central frame sectionpivotally supports a pair of internal spreading bars, including a firstspreading bar 821 which extends within first sleeve 813 and a secondspreading bar 823 having a ratchet or detent structure (to be described)which extends within second sleeve 817.

Although not shown in FIGS. 50 and 51, the spreading bars 821 and 823will preferably have an internal gear mesh so that both will preferablyhave an equal angular displacement with respect to the central hinge box811. The articulation within the central hinge box 811 will enable theselection of three angular frames of reference with regard to thesurface of a patient, namely the angle of first sleeve 813, the angle ofcentral hinge box 811, and the angle of second sleeve 817. Where otherobjects, such as retractors, light sources etc have to be anchored,three reference angle surfaces are available.

The spreading bars 821 and 823 are thus axially fixed with respect tothe central hinge box 811, with the spreading bars 821 and 823 axiallyslidable within the first and second sleeves 813 and 817. Manymechanisms can be utilized to fix the position of the spreading bars 821and 823 within the first and second sleeves 813 and 817. One suchmechanism is show schematically in its most rudimentary form in FIG. 38as including a pivot support 825 which supports a lever 827. The lever827 operates against a spring 829 and operates an engagement member 831with respect to detent structures 833 located on the spreading bars 823.These structures form a first ratchet stop 835. Operational depressionof the lever 827 disengages the detent structures 833 of the spreadingbar 823 to slide within the sleeve 817 and releasing the lever 827enables the spring 829 to act to cause engagement of the engagementmember 831. With this mechanism, or a similar mechanism, the expansionof the expandable frame system 751 can be controlled, with the expansionof the second lateral frame member 803 away from the central hinge box811. Similarly the first lateral member 801 is independently movableaway from central hinge box 811 with the use of a mechanism similar tothe one shown with respect to the pivot support 825, lever 827,spreading bar 823 engagement member 831, and detent structures 833.

The detent structures 833 could be made triangular shaped for sliding inone direction with some form of fixation hold against movement in theother direction. A second mechanism similar to the one shown withrespect to the pivot support 825, lever 827, spreading bar 823engagement member 831, and detent structures 833 is omitted from FIGS.50 and 51 for simplicity. Regardless of the structure, the expandableframe system 751 can be exactly positioned. Other assisted mechanismscan be employed, including a threaded member or a pinion or other devicewhich will give the user mechanical advantage in extending theexpandable frame system 751. Further, the fittings illustrated,including pivot bars 781 & 783 with circular lands 785 and slip fittinginto support fittings 787, as well as the pivot bearing fitting 791 andcooperating fitting 793 suggest that the expandable frame system 751 maybe added to the operating theater after the first and second curvedtubes 753 and 757 have been employed into the surgical opening. Thiswill free the surgeon to position the first and second curved tubes 753and 757 without having to handle the supporting frame members.

Between the other ends of the first lateral member 801 and secondlateral frame member 803 the second telescoping frame member 807 alsohas a central hinge box 811. Again, the central hinge box 811 which ispositioned between a first sleeve 813 and a second sleeve 817. Thecentral frame section pivotally supports a pair of internal spreadingbars, including the first spreading bar 821 within first sleeve 813 andthe second spreading bar 823 which extends within second sleeve 817.

The interfit between the first and second sleeves 813 and 817 and thefirst and second spreading bars 821 and 823 in both the first and secondtelescoping frame members 805 and 807 is expected to be of sufficientlytight tolerance so that both of the central hinge boxes 811 remaindirectly across from each other to enable a common effective pivot axis.If the latch mechanism supported by the second lateral frame member 803is released the second lateral frame member 803 should move away fromthe central hinge box 811. In other words, one of the central hingeboxes 811 should not displace to a position other than directly acrossfrom each other.

The second telescoping frame member 807 could have the same mechanism asthe first telescoping frame members 805, but a slightly differentmechanism is shown in order to emphasize the variability which can beemployed with respect to the expandable frame system 751. A retentionhousing 837 is attached to second sleeve 817 and houses a lock pin 839and a spring 841 which urges it into the second sleeve 817 where itlockably interfits with the detent structures 833. These structures maybe collectively referred to as a second ratchet stop 843. The expansionof the expandable frame system 751, if properly toleranced will enablethe right and left sides to be independently controlled in movementtoward and away from the away from the central hinge box 811. Theactuation of one release mechanism will enable balanced displacement ofits associated first or second lateral members 801 and 803.

Movement of the associated first or second lateral members 801 and 803by one of the latches shown gives a parallel distance separation of thefirst curved tube 753 with respect to the second curved tube 757,regardless of their respective angular positions (assuming nointerference). However, the angularity of the first and second curvedtube 753 and 757 are set by the movement of the threaded member 795. Assuch, the expandable frame system 751 enables independent angularityadjustment for the first and second curved tube 753 and 757 andindependent parallel separation for the first and second curved tube 753and 757 based upon expansion of the frame.

Other features seen in FIGS. 50 and 51 include a support tang 845 and apair of manipulation sphere projections as spreader projections 847 toassist in manually manipulating the expandable frame system 751. FIG. 51illustrates a condition in which the expandable frame system 751 is inan expanded orientation, with first lateral member 801 and secondlateral frame member 803 equally expanded from central hinge box 811.Either of the first and second lateral members 801 and 803 could havebeen extended from the central hinge box 811. This feature gives thesurgeon the flexibility to adjust the positioning of the central hingebox 811. The central hinge box 811 may also have support structures forother instrumentation, including bores 849 in the central hinge box 811such as a bookwalter support (to be shown). Bores 849 can be used forlocational registry or for threaded attachment. A bookwalter device isespecially useful for supporting an additional retractor, in addition tothe first and second curved tubes 753 and 755.

Referring to FIG. 52, a side view of the system of FIGS. 50-51illustrates further details. The angle of the incline of the upperflared portions 755 and 759 are illustrated. A scale 851 helps thesurgeon to ascertain the depth to which the first and second curvedtubes 753 and 755 are inserted into the patient (with the additionalconsideration of any further extension which may be added to the firstand second curved tubes 753 and 755).

One possible configuration for the first and second curved tubes 753 and755, include the use of an upper tube portions along with a lowerextension. The scale 851 could also be utilized, in conjunction with theextension to indicate depth. A notch 853 in each of the first and secondcurved tubes 753 and 755 can be used as a reference surface to engage anextension. Another surface can include a raised portion or depressedportion matched to an extension (as will be shown) in each of the firstand second curved tubes 753 and 755.

FIG. 53 illustrates a double pivot hinge fitting within the centralhinge box 811. A pair of threaded members 861 extend into machinedspaces within central hinge box 811 and hold the spreading bars 821 and823 into a close proximate location such that the complementary gearteeth 863 located on the abutting ends of the spreading bars 821 and 823intermesh with each other. This arrangement insures that the angulardisplacement of the spreading bars 821 and 823 with respect to thecentral hinge box 811 will be equi-angular. This is shown in FIG. 54where the angle γ on both sides indicates equi angular displacement.

Referring to FIG. 55, a top view of the central hinge box 811illustrates a bookwalter retractor device 871 mounted on the uppersurface of the central hinge box 811. The bookwalter device has acentral through bore 873 through which a retractor rail or extension maypass. Typically the retractor extension (not shown) will have a seriesof detents similar to the detents 833 seen in FIG. 53. As the detentsemerge from the through bore 873, they are engaged by a pivoting latch875 which operates under urging force from a spring 877. A turnbuckle orother force control structure would enable operation of a gear mechanismto move any type of “east west” retractor blades towards or away fromthe center.

Referring to FIG. 56, a plan view is shown of a remote force retractionsystem employing many of the structures seen in FIGS. 50-55, but with aremote force system such as disclosed and shown in U.S. Pat. No.4,747,394, to Robert S. Watanabe, and incorporated by reference herein.The technique of application of remote force to leave the surgical fieldopen as applied to the expandable frame system 751 is seen as an openminimally invasive expansion system 901. At the surgical field, many ofthe components previously seen have the same numbering.

A pinion box 903 carries a (removable) key insertable gear 905 seeninside an aperture 907 having teeth 911 which engage a linear gear 913on a first rack 915, and which also engage linear gear 917 on a secondrack 919. To enable the pinion box 903 to move independently andproportionately with regard to structures through which the rack 915passes, rack 915 is fixedly attached to a first main support 921 whilerack 919 is fixedly attached to a second main support 923. As the gear905 is turned clockwise, the rack 915 freely feeds through an aperture931 (seen in dashed line format) in second main support 923, through thepinion box 903 and pushes first support 921 father away from the pinionbox 903. At the same time, the gear 905 pushes the rack 919 freely feedsthrough an aperture 933 (seen in dashed line format) in first mainsupport 921, through the pinion box 903 and pushes second support 923farther away from the pinion box 903.

The result is that two strong support members, namely first support 921and second support 923 are being forced away from each other remotely,by the turning of the key insertable gear 905. Note that the areas oneither side of the first and second curved tubes 753 and 755 are clearto enable other structures to be employed, either unsupported, orindependently supported, or possibly supported from structures whichsupport first support 921 and second support 923.

A ratchet latch lever 935 is mounted is mounted to pivot with respect tofirst support 921 by the action of a spring 937. The ratchet latch lever935 is fork shaped to fit around the tip fixed end of rack 914 and toactuate an internal latch 939 which operates within the first support921 between the first rack 915 and second rack 919.

Also seen is a hinge 941 on first support 921, and a hinge 943 on secondsupport 923. The hinges 941 and 943 should preferably have the sameangular range and would ideally be from about zero degrees (flat) toabout fifteen degrees down with the hinges 941 and 943 rising to formthe apex. The hinges 941 and 943 permit the lateral force components tobe angularly sloped down, or draped to provide an angled workingpresentation, and to take up less lateral space in the same plane as theworking area. Beyond the hinges 941, the first support 921 is connectedto a first extended support 945 while the second support 923 isconnected to second extended support 947.

Both the first and second extended supports 945 and 947 include angularextensions 949 which support the support fittings 787 and otherstructures previously shown. The first and second extended supports 945and 947 also support tilt screw knob 797 and manipulation sphereprojections as spreader projections 847. The support details for thefirst and second curved tubes 753 and 755 is essentially the same as wasshown for FIGS. 50 & 51.

In addition, an optional pair of tilt fittings enable the first andsecond extended supports 945 and 947 to tilt where it may be moreadvantageous to locate open minimally invasive expansion system 901 overportion of a patient's body which is angled. A first tilt adjustmentfitting 951 can be used to provide tilt to the main extent of firstextended support 945, while a second tilt adjustment fitting 953 can beused to provide tilt to the main extent of second extended support 947.Typically the first and second tilt adjustment fittings 951 and 953 willbe used to set the tilt before an operation begins. As to both of thefirst and second tilt adjustment fittings 951 and 953, a support plate955 is rigidly supported by the portion of the respective first andsecond extended supports 945 and 947 nearest the hinges 941. The supportplate 955 supports a retention housing 837. The retention housingincludes a lock pin 839 and a spring 841 which urges it throughapertures of the support plate 955 and across to a selector plate 957.As to both of the first and second tilt adjustment fittings 951 and 953,the selector plate 957 is rigidly supported by the portion of therespective first and second extended supports 945 and 947 on the otherside of the respective first and second tilt adjustment fittings 951 and953.

Although shown in somewhat schematic view, a tilt pin 961 joins portionsof first extended support 945 rigidly while enabling the tilting of theportion of the first extended supports 945 on one side of the first tiltadjustment fitting 951 to pivot with respect to the portion of the firstextended supports 945 on the other side of the first tilt adjustmentfitting 951. Likewise, a tilt pin 963 joins portions of second extendedsupport 947 rigidly while enabling the tilting of the portion of thesecond extended supports 947 on one side of the second tilt adjustmentfitting 953 to pivot with respect to the portion of the second extendedsupports 947 on the other side of the second tilt adjustment fitting953. In reality, in order to transmit the force rigidity, more complexinternal fittings may be utilized. The support plate 955 and selectorplate 957 are simple mechanical mechanisms which are located far enoughoff the axis of pivot to enable selection of a number of angularpositions.

Other structures can be supported from the both the first and secondextended supports 945 and 947. A pair of slot openings 965 at the farends of the first and second extended supports 945 and 947 can supportadditional instrumentation. In addition, the first and second extendedsupports 945 and 947 include structures 965 which may be apertures orprojections or other structures which will enable support to be derivedfor other retractors. A cross support 971 supports a mechanical housing973 through which a linear gear 975 can extend. A retractor 976 (whichcan be of any type) is attached to one end of the linear gear 975. Ahand wheel 977 operates a gear 979 which moves the linear gear 975through the housing 973. This assembly is a first cross supportedretractor set 981. A second cross supported retractor set 983 is alsoshown. This gives the surgical practitioner good control and leverage tooperate the “north-south” retractors.

An illustration of an extension previously mentioned is illustrated inFIG. 57 which illustrates a top view of a curved extension 991 standingalone. Curved extension 991 may have several pair of inwardly directedmembers 993 (or a single large inwardly directed member 993) forengagement against the notches 853 seen in FIG. 52. An inwardly directedangled “snap” protrusion 995 springs into a matching opening on eitherof the first and second curved tubes 753 and 755. The curved extension991 will fit on the outside of the matching first or second curved tubes753 and 755 and the force on the curved extension 961 is expected to beinward at its lower extent during spreading.

Referring to FIG. 58, a side semi-sectional view is shown. A lowerportion of first curved tube 753 having groove 853, and a slot 997 isseen in a sectional view. Adjacent the semi section curved tube 753 isthe curved extension 991 in an attached position. The upper end of henotch 853 fixes against up motion, and the slot 997 fixes against downmotion when it engaged with inwardly directed angled “snap” protrusion995. A stable support relationship is shown.

Referring to FIG. 59, a view looking down into the inside of thecombination of the first curved tube 753 and curved retractor tubeextension 99 of FIGS. 57 and 58. It can be seen how the large inwardlydirected members 993 wrap around the groove 853 and can be slid upwardlyuntil the inwardly directed angled “snap” protrusion 995 engages.

Referring to FIG. 60, a view looking down onto the outside of thecombination of the first curved tube 753 and curved retractor tubeextension 99 of FIGS. 57-59 is seen. In addition, the pivot bar 781 withcircular lands 785 are also seen below the pivot bearing fitting 791,for reference. The large inwardly directed member 993 is partially shownin dashed line format. The bottom of the curved extension 991 may be ofany shape.

Referring to FIG. 61, an exploded view of a frame retractor system 1001is seen. The articulation of the frame retractor system 1001 is achievedby using a main outer first frame section 1003 which laterally overlapsa smaller laterally inner second frame section 1005. The frame sections1003 and 1005 are joined and circumferentially envelop a first retractormember 1007 and a second retractor member 1009. As seen in the earlierembodiments, each degree of motion achieved in retraction, namelyseparation and independent angular articulation each require a series ofactuators and it may be desirable to reduce the number of actuators bothfor simplicity and quick controllability. In the configuration seen inFIG. 61, the angular articulation of the second retractor member 1009 issurrendered with respect to the second frame section 1005, but thesecond frame section 1005 is made limitingly pivotable with respect tothe first frame section 1003.

Beginning further discussion at the left of FIG. 61, a threaded actuator1111 includes a threaded shaft 1113, an expanded diameter actuator knob1115, and a rotation capture fitting 1117 which will enable the threadedactuator 1111 to be captured axially and yet turn. The threaded actuator1111 threaded shaft 1113 engages an internally threaded bore 1119 withinthe second frame section 1005 to enable it to be axially moved throughthe second retractor member 1009.

Second frame section 1005 includes a pair of internally disposed slots1121, each of which is interrupted by a vertical accommodation slot1123. Immediately adjacent the internally disposed slots 1121 areinternally threaded bores 1125. The uppermost ends of the overall “U”shape of the second frame section 1005 includes an angled portion 1127which is used in combination with other structures to limit the amountof pivot of the second frame section 1005 with respect to the firstframe section 1003.

Second retractor member 1009 has thickened structurally reinforced upperhead portion 1131 having a pair of outwardly disposed tongues 1133 whichslidably fit within the slots 1121. Second retractor member 1009 has alower extension member 1135 which may include an insertion accommodationslot 1137. The insertion accommodation slot 1137 has a lower extentwhich curves into the lower extension member 1135 to guide the terminalend of any member inserted into the insertion accommodation slot 1137inwardly. Insertion accommodation slot 1137 has an upper end which opensfrom an upper surface of the reinforced upper head portion 1131.

A set screw 143 is seen over and insertable into a threaded bore 1145which leads into a position to partially obstruct a bore (not seen inFIG. 61) and capture the rotation capture fitting 1117 within thethickened structurally reinforced upper head portion 1131.

The first retractor member 1007 also has a thickened structurallyreinforced upper head portion 1151, but has a pair of pivot bores 1153,one of which is visible in FIG. 61. First retractor member 1007 also hasa lower extension member 1155 which may also include an insertionaccommodation slot 1157. The insertion accommodation slot 1157 has alower extent which also curves into the lower extension member 1155 toguide the terminal end of any member inserted into the insertionaccommodation slot 1157 inwardly. Insertion accommodation slot 1157 hasan upper end which opens from an upper surface of the reinforced upperhead portion 1151.

From an upper surface of the reinforced upper head portion 1151, anupper actuation block 1161 is seen as having a key slot 1163 extendingvertically throughout its length. The vertical length of the key slot1163 enables a member to both pull and push the upper actuation block1161 as it angularly tilts since the key slot 1163 will operate toenable pushing and pulling throughout a range of angles assumed by thefirst retractor member 1007.

First frame section 1003 includes a more distal pair of frame pivotbores 1171, which are aligned with each other and also alignable withthe internally threaded bores 1125 of second frame section 1005. Firstframe section 1003 also includes a less distal pair of internallythreaded bores 1173, which are aligned with each other and alsoalignable with the pair of pivot bores 1153 of the reinforced upper headportion 1151 of the first retractor member 1007. A pair of internallythreaded bores 1173 are engaged by a pair of externally threaded setscrews 1175 to gather support to further engage pivot bores 1153 carriedby the thickened structurally reinforced upper head portion 1151 of thefirst retractor member 1007. Threaded set screws 1175 enable firstretractor member 1007 to pivot with respect to first frame section 1003.

Generally, the first frame section 1003 has a first level which includesthe more distal pair of frame pivot bores 1171 and the less distal pairof internally threaded bores 1173. This level may be on a correspondingfirst level of second frame section 1005 and a same first level onsecond frame section 1005 is seen to include the internally threadedbores 1125, and the internally threaded bore 1119. As a result, thethreaded actuator 1111 acts to move the second retractor member 1009 ata level directly across from the pivoting connection of the pivotingconnection of the first retractor member 1007 to the first frame section1003 and directly across from a pivoting connection of first framesection 1003 to second frame section 1005 (as will be shown).

A second level of first frame section 1003 is seen as a raised fitting1181. The raised fitting 1181 is a block which supports an internallythreaded bore 1183 at a second level, above the first level occupied bythe more distal pair of frame pivot bores 1171 and the less distal pairof internally threaded bores 1173.

To the right of internally threaded bore 1183, a threaded actuator 1191includes a threaded shaft 1193, an expanded diameter actuator knob 1195,and a rotation capture fitting 1197 which will enable the threadedactuator 1191 to be captured horizontally within the upper actuationblock 1161 key slot 1163. Capture of the rotation capture fitting 1197will allow it to urge the upper actuation block 1161 forward andrearward to cause the first retractor member 1007 to pivot. The key slot1163 will continued engagement of the rotation capture fitting 1197regardless of the angle of the first retractor member 1007.

A pair of main threaded members 1199 each have an externally threadedportion 1201 and a knob 1203. The threaded portions pass through themore distal pair of frame pivot bores 1171 and threadably engage theinternally threaded bores 1125 of the second frame section 1005. Theknobs 1203 of the pair of main threaded members 1199 can be tightened tofix the angle of the first frame section 1003 with respect to secondframe section 1005. Also seen is a small bevel cut 1205 on the thickenedstructurally reinforced upper head portion 1151 to better enable thethickened structurally reinforced upper head portion 1151 to tiltforward.

Referring to FIG. 62, a view of the assembled frame retractor system1001 is seen. The co-planarity of the first and second frame sections1003 and 1005 is seen. In the assembled position, it is more readilyseen that the threaded actuator 1191 can actuate the upper actuationblock 1161 away from the raised fitting 1181. It can also be seen thatthe co-planarity of the first and second frame sections 1003 and 1005can be maintained even as the thickened structurally reinforced upperhead portion 1131 and lower extension member 1135 move parallel to theleft.

Referring to FIG. 63, a perspective view of the frame retractor systemfrom the same perspective as seen in FIG. 61 is illustrated as beingfitted with a fiber optic illuminator seen as a length of fiber opticcable 1211 which is guided into the insertion accommodation slot 1137.As could be noted from FIGS. 61 and 62, the slot is a key-type slothaving an opening into the inside of the lower extension member 1135.The fiber optic cable 1211 can thus be set to emit at a terminal end1213, any point near the terminal end, or along the length of the lowerextension member 1135 through the portion of the slot along the lengthof the lower extension member 1135.

Also noted in FIG. 63 is the upward angular displacement of the secondframe section 1005 with respect to the first frame section 1003. Notethat the pivot axis is about a line between the knobs 1203, and throughthe more distal pair of frame pivot bores 1171 and pair of pivot bores1153 which were better seen in FIG. 61. Turn arrows are shown around theknobs 1203 as they can be slightly loosened or tightened to control thetension and capability to hold or change the angle of the second framesection 1005 with respect to the first frame section 1003.

Also note that regardless of the angular position of the second framesection 1005 with respect to the first frame section 1003 seen in FIGS.61 and 62 that the threaded actuator 1111 can be independentlymanipulated to increase or decrease the distance the lower extensionmember 1135 occupies with respect to the lower extension member 1155.Independently of this, threaded actuator 1191 can be used to determinethe angle which lower extension member 1155 takes with respect to firstframe section 1003. The angular separation of the lower extension member1135 occupies with respect to the lower extension member 1155 seen inFIG. 63 is due to the angular position of the second frame section 1005with respect to the first frame section 1003. Further separation of thelower extension member 1135 occupies with respect to the lower extensionmember 1155 can be achieved by actuation of the expanded diameteractuator knob 1195.

FIG. 64 is a top view of the frame retractor system 1001 seen in FIGS.61-63. Also seen an anchoring structure 1221 held in by a threadedmember 1223. The dashed line portions of the drawing of FIG. 64illustrate the action in moving the thickened structurally reinforcedupper head portion 1131 and lower extension member 1135 along the secondframe section 1005 by using the pair of outwardly disposed tongues 1133within the pair of internally disposed slots 1121.

Referring to FIG. 65, a bottom view of the frame retractor system 1001seen in FIGS. 61-64 illustrates the nature of the insertionaccommodation slots 1137 & 1157.

Referring to FIG. 66 a plan view of the frame retractor system 1001 isseen. An additional structural connector 1227 is seen connected to theanchoring structure 1221.

Referring to FIG. 67, a wire retractor 1251 is seen. Wire retractor 1251has a scissors rear portion 1253 which is shown in a horizontal positionand a generally vertical front portion 1255. As shown, the scissors rearportion may have a ratchet mechanism 1257 for helping to hold thescissors portion 1253 in a closed position which will hold generallyvertical front portion 1255 in an open position.

Generally vertical front portion 1255 includes a pair of relatively thinmembers 1261 and 1263, which are connected to scissor arms 1265 and1267, respectively. Thin member 1261, after an angular change 1271 fromscissor arm 1265, includes a somewhat square inward detour as anaccommodation portion 1273. Likewise, thin member 1263, after an angularchange 1275 from scissor arm 1265, includes a somewhat square inwarddetour as an accommodation portion 1277.

Below and beyond the accommodation portions 1273 and 1277 each of thethin members 1261 and 1263 have a pair of wing extensions 1279. The wingextensions 1279 limit the ability of the relatively thin members 1261and 1263 to move past one another, and limit the amount that theaccommodation portions 1273 and 1277 actually do move past each other aswill be seen.

Below the wing extensions 1279 the relatively thin members 1261 and 1263each turn outward and taper to a point 1281. The point 1281 is used topenetrate muscle and to further stabilize the operational field.Referring to FIG. 68, the relatively thin members 1261 and 1263 areshown in a position separated from each other, with the accommodationportions 1273 and 1277 being separated. The outwardly directed parts ofthe accommodation portions 1273 and 1277 are shown in a position to fitwithin the rounded upper opening of the frame retractor system 1001.This enables the practitioner to perform lateral retraction while“locking” the wire retractor 1251 into a stable position with respect tothe frame retractor system 1001.

Referring to FIG. 69, an isolated view of the generally vertical frontportion 1255 illustrates the wire retractor shown superimposed in acrossing pattern to reduce the width profile for entry into the frameretractor system 1001 of FIGS. 61-66 even when the retractor system 1001is in a position where the lower extension member 1135 is closest tolower extension member 1155.

Referring to FIG. 70, a side view of the frame retractor system 1001illustrates the position in which the wire retractor 1251 takes withinthe frame retractor system 1001. The lower extension member 1135 needonly be slightly separated from the lower extension member 1155 toaccommodate the wire retractor 1251. The wire retractor 1251 is simplyused to hold back tissue which is already stressed below the bottom ofthe lower extension members 1135 and 1155 and need only transmit someretention forces to be effective.

Referring to FIG. 71 illustrates the frame retractor system 1001 andwire retractor 1251 shown with respect to tissue 1285 and which ispositioned over deeper tissues 1282. Note that the pair of wingextensions 1279 are positioned close together. This is the positionwhich the generally vertical front portion 1255 assumes upon insertioninto the lower extension members 1135 & 1155 when lower extensionmembers 1135 & 1155 are in close proximity to each other.

Referring to FIG. 72, a view illustrating the wire retractor 1251 beingopened to a stable open position within the frame retractor system 1001is seen. The tissue 1285 to the sides are held back even where lowerextension members 1135 & 1155 are separated from each other.

Referring to FIG. 73, a manual tool 1283 includes a main handle portion1284 supporting a forward fitting 1285. The fitting 1285 shown includesan internal bore and a key slot 1286. An interchangeable bladeattachment 1287 has a rear end which includes a stop collar 1288 and akey projection 1289 which fits with respect to the key slot 1286. Aworking tip end of the interchangeable blade attachment 1287 includes apair of oppositely disposed triangular blades 1288.

Referring to FIG. 74, a different interchangeable blade attachment 1289is shown as having a flat rounded end 1289. Referring to FIG. 75, amanual tool 1290 is shown as having a slip fitting 1291 with manualregister. A slip ring 1292 is movable toward the handle portion 1284 tounlock and away from the handle portion 1284 to lock. FIG. 76illustrates a view looking into the slip fitting 1292 and illustratesthe concentric location of the slip ring 1292 surrounding a split ringportion 1293. A registry block 1294 is seen which insures that theinterchangeable blade attachment 1449 cannot rotate on its axis whensupported by the main handle portion 1443.

Referring to FIG. 77, a top view of a further embodiment of a frameretractor system 1301 is shown. Referring to FIG. 78, a bottom view ofthe embodiment of FIG. 77 is shown. Referring to both FIGS. 77 and 78, aframe retractor system 1301 includes a first main frame member 1303shown to the left and which has an overall outer dimension generallymatching that of a second member section 1305. The tops and undersidesof the first and second main frame members 1303 and 1305 have formeddepressions 1307 which are fitted with threaded bores (not shown) whichfit with a series of threaded members 1309 and can be used to securelylock down any matching structure, with an inner contour of thedepressions 1307 to match the outer contour of an object to be securedto first and second main frame members 1303 and 1305. One such object isshown as an anchoring structure 1311 having a curved portion matching ancurved portion of the depression 1307.

The first main frame member 1303 surrounds a first inner pivotable framemember 1313. A pair of pivot pin members 1315 are shown as extendingthrough bores 1317 at the opposite sides of the first main frame member1303 and into blind pivot bores 1319 in the second frame section 1305.The pivot pin members 1315 may preferably have a threaded exteriorengaging matching threads in bores 1319 to securely lock the pivot pinmembers 1315 in place.

The first main frame member 1303 is pivotally connected to the secondmain frame member 1305 by a similar pivoting arrangement. Pivot pins1323 extend through bores 1325 in the first main frame member 1303, andinto through bores 1327 in the second main frame member 1305. The pivotpins 1323 extend short of interference with an internal groove 1329.

The first inner pivotable frame member 1313 supports a first retractorhalf 1331 which includes a thickened structurally reinforced upper headportion 1333 and a lower extension member 1335. The upper head portion1333 is sized to fit closely within the first inner pivotable framemember 1313 to facilitate quick change out. A pair of rotational locks1337 secure the structurally reinforced upper head portion 1333 withrespect to the first retractor half 1331. With this method andconfiguration, different sized retractors can be quickly selected andlocked into the frame retractor system 1301 to enable retractionstructures of different shape, depth, diameter and different accessorycapability, to be used with the frame retractor system 1301. Rotationallocks 1337 can be threaded members which lock the first retractor half1331 by securing the top edge of the reinforced upper head portion 1333down onto the inner pivotable frame member 1313. Rotational locks 1337can also be cam members which rotate protrusions into slots carried bythe reinforced upper head portion 1333.

The second frame member 1305 supports a first inner translatable framemember 1341 which is linearly translatable within the internal groove1329 in the second frame member 1305. The first inner translatable framemember 1341 has a tongue 1343 which fits within the internal groove 1329and has a length and other dimensions sufficient to stably support thefirst inner translatable frame member 1341 with respect to the secondframe member 1305.

The first inner translatable frame member 1341 supports a secondretractor half 1345 which includes a thickened structurally reinforcedupper head portion 1347 and a lower extension member 1349. The upperhead portion 1347 is also sized to fit closely within the first innertranslatable frame member 1341, and is held in place by a pair ofrotational locks 1337 in the same manner as upper head portion 1347.Both first and second retractor halves 1331 and 1345 can be quickly andeasily changed. Also seen in the underside view of FIG. 78 are bores1351 in which the pair of rotational locks 1337 may operate.

There are three main mechanical controls seen in FIGS. 77 & 78. At theleft side, a knob 1355 is attached to a threaded member 1357 which isthreadably engaged into a raised block 1359 mounted atop first mainframe member 1303. The threaded member 1357 continues beyond thethreaded portion and terminates in a ball shaped fitting 1361. Ballshaped fitting 1361 is engaged in the axial direction by a rotationalfitting block 1363. The rotational fitting block 1359 enables thethreaded member 1357 to be urged axially forward and rearward by turningthreaded engagement with the internally threaded raised block 1359 whileurging the rotational fitting block 1363 toward and away from the raisedblock 1359 to cause the first inner pivotable frame member 1313 to pivotwith respect to the first main frame member 1303.

At the right side a knob 1365 is attached to a threaded member 1367which is threadably engaged into a bore 1369 within second main framemember 1305. Threaded member 1367 continues beyond the threaded portionand terminates within first inner translatable frame member 1341. Thethreaded member 1367 has a groove 1371 for interfitting with a ring lockfitting 1373. The combination of the groove 1371 and ring lock fitting1373 enables the threaded member 1367 to freely rotate within the firstinner translatable frame member 1341 to cause the first innertranslatable frame member 1341 to be moved along internal groove 1329.

As a result of the first two controls, the separation and angularity ofthe lower extension members 1335 and 1349 can be independentlycontrolled. A third control controls the angularity of the first mainframe member 1303 with respect to the second frame member 1305, and cansomewhat equalize the angular position of the lower extension members1335 and 1349 with respect to the average angle of the first and secondmain frame members 1303 and 1305.

Best seen in the lower portion of FIG. 77, an adjustment knob 1375 isattached to a threaded member 1377. At the opposite end of threadedmember 1377 a ball fitting structure 1379 is seen. The ball fittingstructure 1379 rotatably fits within a rotational block fitting 1381which may have a top opening to allow the threaded member 1377 to berotated upward to disengage the rotational block fitting 1381.

The threaded portion of the threaded member 1377 fits inside a threadedsupport block 1383 having at least a portion of an internal spacethreaded (as shown in FIG. 77). A detent mechanism may be suppliedwithin the threaded support block 1383, including a threaded member 1385capturing a spring 1387 which urges a detent ball 1389 into contact withthe threads of threaded member 1377. Opposite the detent ball 1389 areat least a partial set of internal threads 1391 are seen. Where theinternal threads 1391 are only lateral threads, the threaded member 1385may be lifted up, out of contact with such internal threads 1391. Thistype of action is desirable where an obturator 33, 215 or 241 are or maybe used to set the angular displacement of the lower extension members1335 and 1339.

In this case, and depending upon the detent setting, the surgeon canselect between disengagement and remaining engagement of the mechanism,hereafter referred to as frame angle mechanism 1393 including adjustmentknob 1375, threaded member 1377, ball fitting structure 1379, rotationalblock fitting 1381, threaded support block 1383, threaded member 1385,spring 1387 and a detent ball 1389, and internal threads 1391. The frameangle mechanism 1393, being located to the side of the working space,can be re-engaged at any time by turning the knob 1375 and threadedmember 1377 to a position corresponding to the angular relationship ofthe first main frame member 1303 with respect to the second frame member1305.

Also seen is an optional fiber optic system 1395 which can be utilizedwith the frame retractor system 1301 or any frame retractor systemdisclosed. The fiber optic system 1395 may be a laser source poweredremotely, or it may simply be a support for a guided fiber optic. It isshown as being secured by the threaded members 1309 and has a terminus1397 extends into the

Referring to FIG. 79, a sectional view taken along line 79-79 of FIG. 77illustrates further details of the pair of pivot pin members 1315 andpivot pins 1323. Also seen more clearly is the internal groove 1329.

Referring to FIG. 80, a sectional view taken along line 80-80 of FIG. 77illustrates further details of the inside of first inner translatableframe member 1341. The upper extent of the second retractor half 1345 isseen. A lower support surface 1401 is seen to provide an even restingplace for thickened structurally reinforced upper head portion 1347. Arotatable member 1403 is seen as being rotatable between a lockingposition and an unlocked position.

Referring to FIG. 81, a top semi sectional view sectional view focussingon the inside corner of the first inner translatable frame member 1341illustrates further details of the locking mechanism. The upper extentof the second retractor half 1345 is seen. A rotatable member 1403 isseen as being rotatable between a locking position and an unlockedposition. Rotatable member 1403 carries a flat side 1405 which can berotated to face an indentation (to be shown) in either of the reinforcedupper head portions 1333 or 1347 to allow such reinforced upper headportions 1333 or 1347 to slide out of held contact within the firstinner pivotable frame member 1313 and the first inner translatable framemember 1341, respectively. Again, the configuration shown is but one ofmany physical realizations which will allow quick change-out andplacement of the first and second retractor halves 1331 and 1345.

Referring to FIG. 82 one of the indentations 1411 on the structurallyreinforced upper head portion 1347 is seen. In the position shown, therotational lock 1337 has been turned to present the flat side 1405toward the structurally reinforced upper head portion 1347 and thusrotate the rounded side of the rotatable member 1403 out of occupationof the space of the indentation 1411 which allows upper head portion1347 to be removed from the first inner translatable frame member 1341.

Further details of the first and second retractor halves 1331 and 1345are shown in FIGS. 83-87. A broken line is seen in FIGS. 85-87 toillustrate variable length. FIG. 83 is a bottom view of first retractorhalf 1331 looking up into the lower extension member 1335 andillustrating a cutout 1415 which can be considered a partial removal ofmaterial for enhanced ease of insertion and or registry with respect toan obturator, if desired.

FIG. 84 is a bottom view of a second retractor half 1345 and alsoillustrating a complementary cutout 1415. FIG. 85 is a side view thefirst retractor half 1331 shown in FIG. 83 and illustrating a frontprofile of the cutout 1415. FIG. 86 illustrates a matching side view thesecond retractor half 1345. FIG. 87 is a view looking into the curvedback side of second retractor half 1345 and illustrating a profile ofthe cutout 1415 illustrating it to be a an ark removing about half ofthe bottom periphery of the second retractor half 1345.

Further details of a second set of non-circularly curved first andsecond retractor halves are seen in FIGS. 88-92. Again a broken line isseen in FIGS. 88-92 to illustrate variable length. The shape of FIGS.88-92 provide a rectangularization of the viewing profile into the shapeprovided by the retractor halves to open the view space, yet retain thegentle curvature at the edges. FIG. 88 is a bottom view of firstretractor half first retractor half 1421 which includes a thickenedstructurally reinforced upper head portion 1423 and a lower extensionmember 1425. As before, the upper head portion 1423 is sized to fitclosely within the first inner pivotable frame member 1313 to facilitatequick change out. As before indentations 1411 are present so that thestructures shown in FIGS. 83-98 can be utilized with the frame retractorsystem 1301.

FIG. 89 is a bottom view of a second retractor half 1427 and alsoillustrating complementary indentations 1411, upper head portion 1429and lower extension member 1431. FIG. 90 is a side view the firstretractor half 1421 shown in FIG. 88 and illustrating a side profile.FIG. 91 illustrates a matching side view the second retractor half 1427.FIG. 92 is a view looking into the rear back side and curving edges.FIGS. 93 and 94 illustrate a right side and rear view of a retractorhalf 1432 similar to that seen in FIGS. 88-92, but having a bulge 1433at a middle but lower portion of the lower extension member 1425. FIGS.95 and 96 illustrate a right side and rear view of a retractor half 1434similar to that seen in FIGS. 88-92, but having a serrated shape 1435formed along the bottom of the lower extension member 1425. FIGS. 97 and98 illustrate a right side and rear view of a retractor half 1436similar to that seen in FIGS. 88-92, but having a rounded cutout 1437formed along the bottom of the lower extension member 1425.

FIG. 99 illustrates a side elevation view taken somewhat with respect tothe orientation seen in FIG. 77 and looking into the side closest to theadjustment knob 1375. Details which are noticeable include the supportof the threaded support block 1383 from the second frame member 1305. Ascan be seen, the translation control of the first inner translatableframe member 1341 with the knob 1365 is had a lower or first level,generally at the levels of the first and second main frame members 1303and 1305. The pivoting control of first inner pivotable frame member1313 by the controlling engagement of the knob 1355 occurs a secondlevel, above the levels of the first and second main frame members 1303and 1305. It is also noted that the pivoting control of the first mainframe member 1303 with respect to the second frame member 1305, via thecontrol knob 1375, occurs at a level above the levels of the first andsecond main frame members 1303 and 1305.

In reality, translating control of the first inner translatable framemember 1341 with the knob 1365 can be accomplished with a fitting raisedabove the levels of the first and second main frame members 1303 and1305. In addition, the pivoting control of first inner pivotable framemember 1313 with the knob 1355 can occur at the level of the first andsecond main frame members 1303 and 1305 by placing the supportstructures surrounding the pair of pivot pin members 1315 above or belowthe first and second main frame members 1303 and 1305. Similarly, thepivoting control of the first and second main frame members 1303 and1305 with respect to each other can be had by placing the adjustmentknob 1375, threaded member 1377 and ball fitting structure 1379 eitherat the level of the first and second main frame members 1303 and 1305with placement of pivot moment structures elsewhere, or by placing theadjustment knob 1375, threaded member 1377 and ball fitting structure1379 below the frame structure. Other mechanical structures forproviding pivoting control of the first and second main frame members1303 and 1305, each of the first inner pivotable frame member 1313 andfirst inner translatable frame member 1341 may be provided. Such othermechanical structures may provide for separate or integrated controls.Integrated controls may be provided electromechanically or mechanicallyand with or without the use of a microprocessor and pressure sensitivefeedback sensing.

Continuing to refer to FIG. 99, it can be seen that the surgicalpractitioner can adjust the positions of the lower extension members1335 and 1339 in terms of their separation from each other regardless ofangle, their angularity regardless of separation, and independently setthe relationship of the first main frame member 1303 with respect to thesecond frame member 1305. Subsequent FIGS. 94-99 will illustrate onlysome of the movement possibilities.

Referring to FIG. 100, a plan elevational view is shown similar to thatseen in FIG. 99, but with the frame retractor system 1301 show from theopposite side from that seen in FIG. 99. The knob 1365 has caused thethreaded member 1367 to extend outside the second frame member 1305 todraw the first inner translatable frame member 1341 back into the secondframe member 1305 to cause the lower extension member 1349 to move awayfrom the lower extension member 1335.

Referring to FIG. 101, a view from a common perspective as seen for FIG.100 illustrates the activation of knob 1375 has caused the threadedmember 1377 to withdraw through the threaded support block 1383 to causethe first main frame member 1303 to move upwardly to form an angle withsecond frame member 1305. The ability to precisely control the angle offirst main frame member 1303 with respect to the second frame member1305 enables the user to adjust the mean or average position of theframe members 1303 and 1305 with respect to the general orientation ofthe extension members 1335 and 1349. This enables the user to avoidhaving the frame members 1303 and 1305 assume a mean angle with respectto each other which is not somewhat centered by the angle of the framemembers 1303 with respect to frame member 1305.

Referring to FIGS. 102 and 103, a view from a common perspective as seenfor FIGS. 96 and 97 illustrates the activation of knob 1355 has to causethe threaded member 1377 to either withdraw through the threaded supportblock 1359 to cause the first inner pivotable frame member 1313 to tiltthe lower extension member 1335 toward the lower extension member 1349;or conversely to cause the threaded member 1377 to move forward throughthe threaded support block 1359 to cause the first inner pivotable framemember 1313 to tilt the lower extension member 1335 away from the lowerextension member 1349.

With regard to the description for FIG. 101, it can readily be seen thatan angular displacement of the lower extension member 1335 with respectto the lower extension member 1349 as seen in FIG. 102 might be achievedby some angular displacement of the frame members 1303 with respect toframe member 1305, with the remainder of angular displacement beingprovided by actuation of the lower extension member 1335. Angulardisplacement of the frame members 1303 with respect to frame member 1305can occur in either direction if a sufficient length of threaded member1377 is provided.

Referring to FIGS. 104 and 105, a view from a common perspective as seenfor FIGS. 100-103 illustrates the activation of knob 1365 has to causethe threaded member 1367 to either rotatably extend into the internallythreaded second frame member 1305 to cause the first inner translatableframe member 1341 to move toward the first main frame member 1303 tomove the lower extension member 1349 toward the lower extension member1335 (as seen in FIG. 104); or to rotatably withdraw from the internallythreaded second frame member 1305 to cause the first inner translatableframe member 1341 to move away from the first main frame member 1303 tomove the lower extension member 1349 away from lower extension member1335 (as seen in FIG. 99).

Referring to FIG. 106, a top view having a position equivalent to theposition seen in FIG. 104 is shown. The first inner translatable framemember 1341 is in a position having been moved all the way toward thefirst inner pivotable frame member 1313 to have the lower extensionmembers 1335 and 1349 into a circular profile forming a tube. FIG. 106illustrates that the structures which provide angular control of thefirst main frame member 1303 with respect to the second frame member1305 are well clear of the tube formed by the lower extension members1335 and 1349, and even clear of adjacent structures, includingthickened structurally reinforced upper head portions 1333 and 1347, aswell as the first inner pivotable frame member 1313 and first innertranslatable frame member 1341. Essentially, the angular control of thefirst main frame member 1303 with respect to the second frame member1305 is restricted to a dimension which is about the width of the firstand second main frame member 1303 and 1305.

Referring to FIG. 107, the frame retractor system 1301 is shown withrespect to the obturator 33 seen in FIG. 1. The presence of theobturator 33 provides an additional conical spreading structure with theadvance of the ends of the pair of spreading legs 39 and 41 just beyondthe distal most portion of the lower extension members 1335 and 1349. Ashas been seen in FIG. 14, the obturator 33 can provide force at adistance and can assist in separating the first and second main framemember 1303 and 1305.

Referring to FIG. 108 an option for disengagement and re-engagement ofthe frame angle mechanism 1393 is seen. Where the threaded support block1383 has an open upper portion such that the threaded member 1377 can besnapped out of the support block 1383 and pivoted upward, the detentball 1389 can be removed from its rotational fitting block 1363 andremoved. The obturator 33 can then be employed to manipulate the lowerextension members 1335 and 1349. The threaded member 1377 can bereplaced once the lower extension members 1335 and 1349 have been movedto the desired position. Once the threaded member 1377 is replaced, theobturator 33 can be removed. Again, where the spring 1387 and detentball 1389 arrangement is permissibly loose, the obturator 33 can beoperated against the frame angle mechanism 1393 as a force detent. Inthis mode, the obturator would force the extension members 1335 and 1349as the frame angle mechanism 1393 clicks open to a desired position. Inthis arrangement, the obturator 33 does not operate on either of thefirst inner translatable frame member 1341 or first inner pivotableframe member 1313, both of which are expected to be non movable by theobturator 33, but operates on the frame angle mechanism 1393.

Referring to FIG. 109, a variation on the frame retractor system 1301 inFIGS. 77-102 is seen as a frame retractor system 1801. The portion offrame retractor system 1801 generally appearing in the right third ofFIG. 109 is the same as was shown in FIG. 77, and these structures willretain their original numbering. Note that first and second main framemembers 1803 and 1805 are slightly more compact and more closely fittingwith respect to each other.

The frame retractor system 1301 relied upon force structure located in aspaced relationship from the pivot axis, externally located with respectto the frame retractor system 1301 to operate. The relied upon forcestructure for tilt typically involved a threaded member 1357 or 1377which could be seen externally. In both of these cases the axis of thethreaded member 1357 or 1377 were external to the main vertical extentof the main structural members of the frame retractor system 1301. Theaxis of the threaded members 1357 or 1377 can be displaced from thepivot axes they control and provide enhanced mechanical advantage.

The frame retractor system 1801 provides control generally within thevertical limits of a first and second main frame members 1803 and 1805.Mechanical advantage can be achieved by selection of the pitch of thegears which follow. The method of control is to provide a relatively lowprofile knob having a vertical shaft which contains a worm gear. Theworm gear acts upon an gear having an effective horizontal axis toeither tilt a structure equivalent to the prior first inner pivotableframe member 1313 or to tilt the a first main frame member 1803 withrespect to the second main frame member 1805.

Referring to the lower left side of FIG. 109, a first gear works cover1811 is secured by a pair of threaded members 1813. A low profile knob1815 extends upward from the level of the first gear works cover 1811 toprovide for manual user control. A first inner pivotable frame member1821 is similar to the first inner pivotable frame member 1313, but isshown as having some material removed to accommodate the mechanism beingdescribed.

A pair of oppositely disposed pin members include a first pivot member1825 and a second pivot member 1827. The first pivot member 1825 is setto have a terminal portion within first inner pivotable frame member1821 which turns with the first inner pivotable frame member 1821. Thesecond pivot member 1827 need only support the first inner pivotableframe member 1821 and allow it to pivot with respect to the second mainframe members 1805.

The low profile knob 1815 is attached to a worm gear (not seen in FIG.109). Adjacent worm gear (not shown in FIG. 109) an elongate cylindricalgear structure may be located which will rotate with first innerpivotable frame member 1821. Such a gear surface may be located on aspecial gear within the first inner pivotable frame member 1821, or inthe alternative, such a gear surface may be formed on the externalsurface of the first inner pivotable frame member 1821. Since the firstinner pivotable frame member 1821 need only tilt slightly, thearrangement for the pitch of the worm gear assembly can yieldsignificant mechanical advantage. Further, because the angulardisplacement is small, the size of the gear elements (deeper widergrooves) should not be adversely impacted by a relatively highmechanical advantage.

A similar arrangement is had with respect to the angular adjustment offirst main frame member 1803 with respect to second main frame member1805. Referring to the bottom center of FIG. 104, a second gear workscover 1841 is secured by a pair of threaded members 1843. A low profileknob 1845 extends upward from the level of the first gear works cover1841 to provide for manual user control. The low profile knob 1845 andsecond gear works cover 1841 engages a portion of the second main framemember 1805 and moves the angular relationship of the first main framemember 1803 with respect to second frame member 1805.

A pair of oppositely disposed pin members include a first pivot member1847 and a second pivot member 1849. The first pivot member 1847 is setto have a terminal portion within first main frame member 1803 enablesfirst main frame member 1803 to become angularly displaced from secondmain frame member 1805 while securing the pivot point between first mainframe member 1803 and second main frame member 1805.

Again, the low profile knob 1845 is attached to a worm gear (not seen inFIG. 109). Adjacent worm gear (not shown in FIG. 109) may be an elongatecylindrical gear structure will be located which will rotate with firstinner pivotable frame member 1821. Such a gear surface may be located ona special gear within the first main frame member 1803, or in thealternative, such a gear surface may be formed on the external surfaceof the first main frame member 1803, such as the rounded area adjacentsecond main frame member 1805 near the pivot point.

As before, since the first and second main frame members 1803 and 1805can change their relative angular position only slightly, thearrangement for the pitch of the worm gear assembly can yieldsignificant mechanical advantage without sacrificing the size and depthof the gear elements.

Referring to FIG. 110, a bottom view of the frame retractor system 1801is shown and illustrating the underside elements. Referring to FIG. 111,a side view illustrates further details of the frame retractor system1801 seen in FIGS. 109 and 110. This pan semi sectional view illustratesa first worm gear 1851 associated with low profile knob 1815 and asecond worm gear 1853 associated with low profile knob 1845. A firstpivot gear 1861 is seen engaging the first worm gear 1851, while asecond pivot gear 1863 is seen engaging the second worm gear 1853. Thefirst and second pivot gears 1861 and 1863 may be completely circular ormay be semi-circular. The showing of FIG. 110 can be a partial showingor it can be a showing greater than what is provided as the angle oftilt will not be great.

One of the advantages seen in both the frame retractor systems 1301 and1801 is the ability to remove the first and second retractor halves 1331and 1345 vertically. This enables, without moving the overall frameretractor systems 1301 and 1801, the first and second retractor halves1331 and 1345 to be removed or replaced. Removal and replacement can beachieved simply by actuation of the pair of rotational locks 1337. Suchinterchange ability can permit the surgical practitioner to quicklychange out first and second retractor halves 1331 and 1345 for othertypes and depths of retractors, or to remove the retractors in favor ofother structures.

Referring to FIG. 112 the frame retractor system 1301 is shown with thefirst and second retractor halves 1331 and 1345 removed, and with theworking sleeve 35, previously seen in FIG. 1, suspended with a clampfixture 1901. As can be seen, clamped fixture 1901 has a base portion1903 which is attached onto one of the formed depressions 1307 andsecured by the series of threaded members 1309 which remain readilyavailable for quick attachment of any utility structure. Referring toFIG. 113, the base 1903 can be seen as extending across to a horizontalweb portion 1906, and then upward to a strap portion 1907. The end ofthe strap portion is attached to the a nut 201 and bolt 203 assemblypreviously seen in FIG. 25. Other strap supports can be employed on boththe frame retractor systems 1301 and 1801 to enable wide flexibility inuse.

In all of the devices shown, including the retractors devices such asworking sleeves 35, 222, retractors 555, 571, 691, 573, 631, 657, 691,751, 901, 1001, 1301, 1801 and obturators 33, 241, a manual control wasshown including knobs 50, 587, 597, 597, 617, 627, 635, 673, 797, 1115,1195, 1355, 1365, 1375, 1815, 1845 and more, as well as threaded member203, and knob 261. Some are shown as knurled members and others ashexagonal members, but in fact the hexagonal shapes and knurled shapescan be used interchangeably.

Depending upon the size of the tool, its working depth and otherfactors, tremendous working forces can be generated. A review of theliterature illustrates resort to massive mechanical members whichproject far from the medical instrument are often employed to generatethe forces needed. The approach to all of the medical instrumentationherein has been one of low profile, and to occupy no more of thesurgical field than is absolutely necessary. Where the actuation memberslie parallel and close to the patient's body they may be more difficultto actuate in the presence of significant tissue resistance toretraction. Therefore, a sterilizable ratchet has been developed inorder to enable quick, temporary, enhanced mechanical actuation of theretractor members. Mechanical advantage may thus be had based uponmechanical advantage embodied in the particular retractor operationstructure (including obturators) and in addition by a sterilizableratchet tool which gives even more precise control for the medicalpractitioner. Any ratchet engagement is possible. A hexagonal bore couldbe provided within the knurled knobs to facilitate both direct manualand ratchet driven operation.

Referring to FIG. 114 a ratchet actuation tool 3001 is shown. One of theproblems with tools used in surgery is the ability to dis-assemble andsterilize and dis-assemble, if necessary the instrumentation. A ratchetor other common mechanical tool which would otherwise be a great help inthe surgical theater is a problem from a sterilization standpoint. Mostcommonly known mechanisms include closed spaces, snap fit, and are notintended for disassembly. The ratchet actuation tool 3001 utilizesone-way permitted turning with a pair of socket heads and utilizes asimplistic internal mechanism with flow-through liquid wetting.

FIG. 114 is a side view looking through the ratchet actuation tool 3001.The ratchet actuation tool 3001 includes a first socket 3003 having asocket opening 3005 shown in dashed format. A first plate 3009 includesan aperture (not shown in FIG. 114) which provides rotational support. Asecond plate 3011 is spaced apart from the first plate 3009. An “openair” or through opening to the other side is labeled as 3013. To theleft of through opening 3013 is seen a spring 3021, and spring bias post3025 which is seen extending into the first plate 3009. A threadedmember 3027 is seen attaching the end of the spring to a ratchetsprocket engagement head 3029. The ratchet sprocket engagement head 3029engages a sprocket 3031.

All of the components located just above the lower plate 3009, have aliquid gap between those components and either the first plate 3009 andsecond plate 3011, meaning that the components are not tightly jammedtogether to have a danger of creating significant sealed spaces. Asecond socket 3035 has a socket opening 3037. Second socket 3035 extendsabove second plate 3011. The first socket 3003 includes a through memberhaving a threaded post which a matching threaded bore within the secondsocket 3035 which engages the threaded post. In the case of a right handthread, the turning of the plates 3009 and 3011 and post will cause thesecond socket to be even more securely turned and locked onto the post.The use of a double socket design enables reliance upon turning in onlyone direction.

At the opposite end of the ratchet actuation tool 3001, a spacer clip3045 has a spacer portion 3051 and a threaded bore 3053. A hook portion3055 includes a rising vertical portion and a hook to help hold thesecond plate toward the first plate. A threaded member 3059 holds thespacer clip 3045 down into an accommodation space 3061.

The spacer portion 3051 has a height in excess of the depth of theaccommodation space 3061 which will positively and securely set theheight of the first plate 3009 with respect to the second plate 3011.The threaded member passes through a bore 3065 before it engages thethreaded bore 3053. A groove 3067 is seen to extend partially around acutaway 3069 with the groove to accommodate the forward portion of thehook portion 3055 and the cutaway 3069 to accommodate the bulk of thehook 3055. As can be seen, the removal of the threaded member 3059causes spacer clip 3053 to fall away and frees the first plate 3009 fromthe second plate 3011 at the end opposite the first and second sockets3003 and 3035.

Also shown is a round pivot bar 3071 which is preferably jam fit withina bore 3075 in the first plate 3009 and extends through the ratchetsprocket engagement head 3029 and then loosely through a bore 3077 inthe second plate 3011.

Referring to FIG. 115, a view is shown with the second plate 3011removed, but with the spacer clip 3045 having been re-attached to showits position. Additional elements seen include the round pivot bar 3071and the forward end 3081 of the ratchet sprocket engagement head 3029.The spring 3021 can be seen as acting on the ratchet sprocket engagementhead 3029 to urge the forward end 3081 of the ratchet sprocketengagement head 3029 into locking contact with the sprocket 3031.

The sprocket 3031 is seen as having a square opening 3091. A threadedpost 3093 has threads on the round portion shown and has a lower squaremember for interfitting with the square opening 3091 of the sprocket3031. Referring to FIG. 118, a view with many of the elements seen inFIG. 115 is shown. The jam fit round pivot bar 3071 remains after theassembly consisting of the spring 3021, threaded member 3027, andratchet sprocket engagement head 3029 is removed. Removal of the firstsocket 3003 reveals a first large aperture 3095 through which thethreaded post 3093 extended in the assembled state.

Referring to FIG. 117, a view of the top plate 3009 illustrates a secondlarge aperture 3097. Also seen are the previously mentioned bore 3077,groove 3067 and cutaway 3069. Referring to FIG. 118, a side sectionalview of the first plate 3009 also illustrates a jam aperture 3099previously occupied by the spring bias post 3025. Referring to FIG. 119,a side sectional view of the second plate 3011 illustrates another viewof the second large aperture 3097.

Other figures illustrate further details. Referring to FIG. 120 an endview looking into the first socket 3003 is shown. Referring to FIG. 121,a plan view of the first socket 3003 illustrate the details thereof. Astepped surface 3103 is larger than the first large aperture 3095 andprevents the first socket 3003 from passing through the first largeaperture 3095. A rectangular section 3107 engages square opening 3091 ofthe sprocket 3031. This enables engagement of the ratchet sprocketengagement head 3029 onto the sprocket 3031 to translate into rotationalfixation of the first socket 3003. Above the rectangular section 3107 isa threaded section 3109 which will engage a matching threaded bore inthe second socket 3035.

Referring to FIG. 123 a rear view of the second socket 3035 reveals athreaded bore 3111. Note that the ratchet sprocket engagement head 3029is set to turn the threaded section 3109 clockwise into the threadedbore 3111. If the first and second plates 3009 and 3011 move in anopposite direction the sprocket 3031 moves in the other direction andsimply causes the ratchet sprocket engagement head 3029 to click pastthe sprocket teeth. FIGS. 124 and 125 illustrate further details of thesecond socket 3035.

Referring to FIGS. 126 and 127 a plan and end view of the ratchetsprocket engagement head 3029 is seen in an unengaged position andwithout threaded member 3027. Newly seen is a main ratchet sprocketengagement head aperture 3121. Also seen is the threaded bore 3125 whichis normally engaged by threaded member 3027 to hold spring 3021 inplace.

Referring to FIG. 128, a plan view of the sprocket 3031 is seen.Referring to FIG. 129, a plan view looking downward on the spacer clip3045 illustrates further details of the spacer clip 3045, and especiallythe relationship of the threaded bore 3053 to the forward hook portion3055.

FIG. 130 is an exploded sectional detail illustrating the relationshipof the first plate 3009 and second plate 3011, how the spacer clip 3045is secured to the first plate 3009, how the spacer clip 3045 secures thesecond plate 3011 and how the spacer clip 3045 acts to control thespacing between the first and second plates 3009 and 3011.

The retractor systems thus described permit the following surgicalprocedure, some steps of which may be omitted and the order of which isnot necessarily in accord with the order of steps as presented:

-   1. Locate a proper incision location (such as by fluoroscopy).-   2. Insertion of a Guide Pin to determine a depth from skin to facet    joint, to identify correct surgical level and the best angle of    approach.-   3. Apply the proper length surgical retractor blades to the frame.-   4. Make an appropriate length incision, which may include:    -   (a) one and a half times the largest diameter effective tube for        microdiscectomy procedure    -   (b) two times the effective tube width for two level fusion    -   (c) three times the width for three level fusion-   5. Insert not more than one fascial incisor/tissue dissector over    the Guide Pin and incise the fascia.-   6. Dissect the muscle attachments of the multifidus muscles off the    spinous process, lamina, and transverse process in a longitudinal    direction.-   7. Insert retractor with fitted obturator into the wound and verify    correct placement with fluoroscopy.-   8. Partially expand the obturator and retractor blades then remove    the obturator.-   9. Adjust the frame to the contour of the body with proper flexion    or extension of the frame.-   10. Connect the frame to the operating table or other support if    desired.-   11. Expand the retractor blades sufficient to visualize the planned    surgical procedure.-   12. Dock the tip of the retractor blades to the correct anatomical    site.-   13. Apply the custom Gelpi-type hand held retractor to retract    muscle ingress if necessary.-   14. Proceed with planned surgery.-   15. Make changes of the position as necessary during the surgery and    relax the retractor blades every twenty minutes to allow    recirculation for of the muscles and nerves.

The advantages of performing a surgical procedure with the retractorsystems described in the specification, include, but are not limited tothe following:

-   1. A single entry process can be practiced instead of sequential two    dilation process.-   2. Creation of a surgical field is done only to the necessary    dimension with micro adjustable frame and retractor blades.-   3. The use of an expanding obturator allows controlled separation of    the muscle fibers so as to eliminate shredding and tearing of    muscle.-   4. Customized retractor tips to allow docking on specific bony sites    to further stabilize exposure.-   5. Surgical blade rotation is finely controllable with a threaded    screw device giving both control and mechanical advantage.-   6. The retractor support is adjustable to body contour.-   7. Muscle compression release can be more easily carried out more    often, such as every twenty minutes, for example resulting in less    soft tissue damage.-   8. Once deployed, the retraction system is stable such that    attachment to the operating table may or may not be required.

While the present system has been described in terms of a system ofinstruments and procedures for facilitating the performance of amicroscopic lumbar diskectomy procedure, one skilled in the art willrealize that the structure and techniques of the present system can beapplied to many appliances including any appliance which utilizes theembodiments of the instrumentation of the system or any process whichutilizes the steps of the inventive system.

Although the system of the invention has been derived with reference toparticular illustrative embodiments thereof, many changes andmodifications of the systems shown may become apparent to those skilledin the art without departing from the spirit and scope of the inventivesystem. Therefore, included within the patent warranted hereon are allsuch changes and modifications as may reasonably and properly beincluded within the scope of this contribution to the art.

1. A minimal incision maximal access minimal invasive surgical spineinstrument comprising: a first retractor blade member; a secondretractor blade member; a support having a first member for supportingsaid first retractor blade member and a second member for supportingsaid second retractor blade member, said first member of said supportcontrollably angularly pivotable with respect to said second member ofsaid support about a first pivot axis, and wherein at least one of saidfirst retractor blade member and said second retractor blade member ismovable independent of its associated one of said first member and saidsecond member; and a mechanical linkage configured to rotate said firstmember and said second member in both a first direction and a seconddirection with respect to each other about said first pivot axis, saidmechanical linkage configured to maintain an angular relationship ofsaid first member with respect to said second member, and wherein bothof said first retractor blade member and said second retractor blademember are independently pivotable with respect to the associated saidfirst member and said second member about second and third pivot axes,respectively, said first, second and third pivot axes being coplanar andparallel.
 2. The minimal incision maximal access minimal invasivesurgical spine instrument as recited in claim 1 wherein said mechanicallinkage further comprises a threaded support block supported by at leastone of said first member and said second member, a threaded memberhaving a ball fitting structure and having threads engaging saidthreaded support block, and a rotational block fitting engaging theother of said first member and said second member to enable said firstmember to be controllably pivoted with respect to said second member. 3.The minimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 1 wherein at least one of said firstretractor blade member and said second retractor blade member isindependently translatable with respect to its associated supportmember.
 4. The minimal incision maximal access minimal invasive surgicalspine instrument as recited in claim 3 wherein at least one of saidfirst and second retractor blade members, includes a projection andwherein, its associated support member includes a slot in which saidprojection is guided to facilitate said translating movement.
 5. Theminimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 1 wherein said at least one of said firstretractor blade member and said second retractor blade member translatesas one of the first support member and the second support member movesrelative to the other of the first support member and the second supportmember.
 6. The minimal incision maximal access minimal invasive surgicalspine instrument as recited in claim 1 wherein said at least one of saidfirst retractor blade member and said second retractor blade member hastranslating movement by the movement of least one of said firstretractor blade member and said second retractor blade member within itsassociated support member.
 7. The minimal incision maximal accessminimal invasive surgical spine instrument as recited in claim 1 whereinat least one of said first retractor blade member and said secondretractor blade member is pivotable independent of its associatedsupport member.
 8. The minimal incision maximal access minimal invasivesurgical spine instrument as recited in claim 1 wherein at least one ofsaid first retractor blade member and said second retractor blade memberpivots by a second mechanical linkage for manipulating at least one ofsaid first retractor blade member and said second retractor blade memberwith respect to its associated support member and wherein said secondmechanical linkage further comprises a threaded support block supportedby its associated support member, a threaded member having a ballfitting structure and having threads engaging said threaded supportblock, and a rotational block fitting engaging at least one of saidfirst retractor blade member and said second retractor blade member. 9.The minimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 1 wherein at least one of said firstretractor blade member and said second retractor blade member furthercomprises a frame member and wherein said frame member supports said atleast one of said first retractor blade member and said second retractorblade member.
 10. The minimal incision maximal access minimal invasivesurgical spine instrument as recited in claim 9 wherein at least one ofsaid first retractor blade member and said second retractor blade memberis held within said frame member by at least a pair of rotational lockswhich operate from said frame member by at least one of directly andlaterally.
 11. The minimal incision maximal access minimal invasivesurgical spine instrument as recited in claim 1 wherein said first andsecond retractor blade members each have a proximal end and a distal endand wherein said first and second retractor blade members can beadjusted over a range of angles with respect to each other from a firstextreme such that said distal ends of said first and second retractorblade members are farther from each other than their said proximal ends,and to a second extreme such that the said proximal ends of said firstand second retractor blade members are farther from each other thantheir said distal ends.
 12. The minimal incision maximal access minimalinvasive surgical spine instrument as recited in claim 11 wherein aposition between said first extreme and said second extreme includes aposition where said first and second retractor blade members areparallel to each other.
 13. The minimal incision maximal access minimalinvasive surgical spine instrument as recited in claim 1 wherein atleast one of said first and second retractor blade members includes aspecialized shape which is at least one of an angle cutout portion, abulge portion, a serrated portion and a midline rounded cutout portionnear a distal end thereof.
 14. The minimal incision maximal accessminimal invasive surgical spine instrument as recited in claim 1 whereinsaid first retractor blade member and said second retractor blade membercan move evenly toward and away from each other.
 15. The minimalincision maximal access minimal invasive surgical spine instrument asrecited in claim 1 wherein said support has the shape of a rectangularframe.
 16. The minimal incision maximal access minimal invasive surgicalspine instrument as recited in claim 15 wherein a first side and twocorners of said frame are the first support member and wherein a secondside and two corners of said frame are the second support member.
 17. Aminimal incision maximal access minimal invasive surgical spineinstrument comprising: a first retractor blade member; a secondretractor blade member; a support having a first portion for supportingsaid first retractor blade member and a second portion for supportingsaid second retractor blade member, said first and second portionspivotably coupled about a first pivot axis, wherein a mechanical linkageadjusts and maintains an angular relationship between the first andsecond portions; an internal threaded bore supported by said firstportion; a threaded member having a rotation fitting structure andhaving threads engaging said threaded bore supported by said firstportion of said support; a first rotational fitting associated with saidfirst retractor blade member to enable said threaded member to rotatewith respect to said first rotational tilting and to enable saidthreaded member to move axially to push said first rotational fittingtoward and pull said first rotational fitting away from said firstportion of said support, wherein said first retractor blade member ispivotable about a second pivot axis, said first and second pivot axesbeing coplanar and parallel.
 18. The minimal incision maximal accessminimal invasive surgical spine instrument as recited in claim 17wherein said first retractor blade member is pivotally supported aboutsaid second pivot axis by said support and said first rotational fittingengages said threaded member above said second pivot axis.
 19. Theminimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 18 wherein said first rotational fittingis a rotational fitting block and wherein said threaded member includesa ball shaped fitting engaging said rotational fitting block.
 20. Theminimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 19 and further comprising a threadedsupport block for threadably engaging said threaded member, saidthreaded support block having an upper opening to enable lateraldisengagement of said threaded member for immediate disengagement of apivot position of said first retractor blade.
 21. The minimal incisionmaximal access minimal invasive surgical spine instrument as recited inclaim 17 and further comprising a first inner pivotable frame member andwherein said first retractor blade member is selectively detachable fromsaid first inner pivotable frame member and wherein said first innerpivotable frame member is pivotally supported about said second pivotaxis by said support and wherein said first rotational fitting issupported by said first inner pivotable frame member and engages saidthreaded member above said second pivot axis.
 22. The minimal incisionmaximal access minimal invasive surgical spine instrument as recited inclaim 21 wherein said first retractor blade member is selectivelydetachable from said first inner pivotable frame member by rotationallocks which operate from said frame member by at least one of directlyand laterally.
 23. The minimal incision maximal access minimal invasivesurgical spine instrument as recited in claim 17 wherein said firstretractor blade member is supported for translating movement withrespect to said support.
 24. The minimal incision maximal access minimalinvasive surgical spine instrument as recited in claim 23 wherein saidfirst retractor blade member further comprises: thickened structurallyreinforced upper head portion; a lower extension retractor blade memberattached to said thickened structurally reinforced upper head portionand extending away from said thickened structurally reinforced upperhead portion; a pair of outwardly oppositely disposed tongues, whereinsaid support includes a pair of internally oppositely disposed slotscomplementary to said pair of outwardly oppositely disposed tongues forstably orienting said first retractor blade member and enabling saidfirst retractor blade member to translate with respect to said support.25. The minimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 23 wherein said support has an uppersurface and a lower surface, and wherein said internal threaded bore andsaid threaded member are located between said upper surface and saidlower surface of said support.
 26. The minimal incision maximal accessminimal invasive surgical spine instrument as recited in claim 17,further comprising a first inner translatable frame member having a pairof outwardly oppositely disposed tongues, wherein said support includesa pair of internally oppositely disposed slots complementary to saidpair of outwardly oppositely disposed tongues for stably orienting saidfirst inner translatable frame member, said first retractor blade memberselectively detachable from said first inner translatable frame member.27. The minimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 26 wherein said first retractor blademember is selectively detachable from said first inner pivotable framemember by rotational locks which operate from said frame member by atleast one of directly and laterally.
 28. The minimal incision maximalaccess minimal invasive surgical spine instrument as recited in claim 17wherein said support has the shape of a rectangular frame.
 29. Theminimal incision maximal access minimal invasive surgical spineinstrument as recited in claim 28 wherein a first side and a two cornersof said frame are the first support member and wherein a second side andtwo corners of said frame are the second support member.
 30. The minimalincision maximal access minimal invasive surgical spine instrument asrecited in claim 17 wherein at least one of said first and said secondretractor blade members includes a specialized shape which is at leastone of an angle cutout portion, a bulge portion, a serrated portion anda midline rounded cutout portion near a distal end.